Andrew Carnegie stood “probably no more than 5 feet tall” at age 25 “with a barrel chest and a huge head,” according to author David Nasaw. While Carnegie isn’t always a popular figure in Pittsburgh history, his shrewd investments and ruthless emphasis on efficiency and cost cutting drove the creation of the Mon Valley Works and its early prosperity.

By the time he was 30, he had become rich from speculating in Pennsylvania oil, which replaced whale oil during the Civil War, and he had insider access to key power brokers.

Andrew Carnegie, circa 1919. (Carnegie Museum of Art)

Carnegie understood railroads. He had quickly climbed the ranks of the Pennsylvania Railroad in Altoona, about 100 miles east of Pittsburgh. He left the PRR with the idea of better exploiting his connections there as he invested in new businesses, according to Nasaw’s book “Andrew Carnegie.”

Much of his early wealth was built on “crony capitalism,” Mr. Nasaw wrote. Carnegie and other partners used their insider knowledge or connections to invest in intertwining businesses. As railroad construction kicked into high gear after the Civil War, so did iron production for the rails and bridges they ran on. Carnegie invested in iron.

After Congress opened the door to domestic steel production by passing a tariff on imported steel in 1870, Pennsylvania steel companies launched — notably about 67 miles east of Pittsburgh in Johnstown’s Cambria Iron and near Harrisburg at Steelton with Pennsylvania Steel.

Steel lasted longer than iron. Carnegie toured Henry Bessemer’s steel plant in Sheffield, England, where he was impressed with this new process to make steel more cheaply and quickly and he was determined to get in on the new industry.

When he returned to Pittsburgh, he invested in a new mill at Braddock’s Field in North Braddock along the Mon River using the Bessemer steelmaking process.

At Carnegie’s suggestion, the new mill was named for his old mentor and inside collaborator J. Edgar Thomson, then the “nation’s most respected railroad executive,” according to Mr. Nasaw.

The Braddock mill began producing steel on Aug. 25, 1875, according to the Pittsburgh Post.

Railcars in massive railyards trundled into Pittsburgh, a city enveloped in black soot and smells from the many factories, foundries, refineries, slaughterhouses and other heavy industry along its riverbanks.

Carnegie was just one industrialist building his fiefdom around Pittsburgh in the late 1800s, but he was one of the most successful in the country. He quickly amassed a steelmaking juggernaut, buying the Homestead mill in 1883 and the Duquesne works in 1890.

The towns around these plants burst to life. Braddock’s population jumped from 1,290 in 1870 to 8,561 in 1890. Duquesne was not even incorporated in 1870 but had about 3,800 people when it was in 1891; and Homestead went from 592 in 1880 to 7,911 in 1890.

On Aug. 11 this year, a sound like a clap of thunder hit Clairton. People ran outside and saw black smoke pouring from the Clairton Works plant. A ruptured valve had caused an explosion, killing two men and seriously injuring five other people.

The incident offered a grim reminder of how dangerous working in steel mills can still be, despite safety measures and new technology.

Mike Stout, a Homestead Works crane operator in the 1970s and ’80s, said in an interview, “If I made one wrong move [with the crane], I could take somebody’s fingers off. And I saw many an accident.”

Being crushed by machinery, killed in explosions or burned by molten metal were among the potential hazards on the mill floor. Newspaper squibs of the late 1880s and early 1900s noted injuries from falling joists, men falling from high places and being run over by machinery. In one case, a man hit another in the head with a sledgehammer. On purpose.

The only protective gear was two pairs of wool long underwear, according to the PBS series “Andrew Carnegie: The Richest Man in the World.”

A man fell into a car of hot ore dust and was cremated in 1905 at the Edgar Thomson Works. (Feb. 22, 1905, The Pittsburgh Gazette)

An accident severed a worker’s hand in 1892 at the Edgar Thomson Works. (Oct. 1, 1892, The Pittsburgh Press)

A man fell 28 feet off a scaffold at Edgar Thomson in 1887 and broke his foot, sprained his ankle and injured his back. (July 9, 1887, Post-Gazette)

One worker was angry about another drinking from the communal water bucket and hit the offender in the head with a sledgehammer. (July 5, 1887, Pittsburgh Commercial Gazette)

Three steel mill accidents in 1891 included one man badly burned, another with a crushed arm and a third suffered internal injuries after a stack of rails fell on him. (June 18, 1891, The Pittsburgh Press)

A chip of steel blinded a man in 1902 at the Homestead Works. (March 7, 1902, Pittsburgh Gazette)

Men often skipped meals during their 10- to 12-hour shifts, 5½ to seven days a week, because they had no time to eat. And they sweated so much in the intense heat that one worker said he lost 40 pounds in three months, with the sweat sometimes running down his legs and filling his shoes.

The average steelworker wage in 1890 was just above the poverty line at $10 per week, according to the PBS series.

Burned out, fed up and worked nearly to death, laborers began trying to organize to force management to improve their job conditions. The American labor movement traces some of its roots to the Mon Valley mills, along with one of its most serious setbacks.

In 1888 Carnegie broke a labor strike at Braddock by hiring a private army from the Pinkerton Detective Agency. His methods foreshadowed what was to come.

Andrew Carnegie’s partner Henry Clay Frick, “The King of Coke”, broke the union at the Homestead Works in 1892.
(Heinz History Center)

In 1892, the more infamous Homestead strike erupted over wage cuts and a demand that the plant’s union be dissolved.

Carnegie, away in Scotland, gave his partner Henry Clay Frick authority to deal with the workers any way he saw fit. Frick built a huge fence around the plant and locked out the workers. Then he fired the plant’s 3,800 men.

As Carnegie had in Braddock, Frick hired some 300 armed Pinkerton agents, instructing them to defend the barricaded plant while he brought in non-union labor to replace the fired workers.

Tugboats pulled barges of Pinkertons along the Mon River to Homestead. In the early morning hours of July 6, the townspeople and Pinkertons began firing at each other. The Pittsburgh Press on July 7, 1892, listed nine Homesteaders and two Pinkertons dead, though tallies today vary. The Library of Congress gives 16 deaths; the AFL-CIO says seven workers and three Pinkertons.

When the outnumbered Pinkertons finally surrendered, strikers and townspeople lined up and beat them as they left their barges. Public sympathy for the strike soured as newspapers ran accounts of a reporter hearing “skulls crack” and Pinkertons with “blood rushing down the back of their heads.”

Homesteaders force the surrendering Pinkertons to run a gauntlet.
(The Pittsburgh Post)

Pennsylvania’s governor sent in the state National Guard. Frick was able to restart the mill with non-union labor, according to the Battle of Homestead Foundation.

The strikebreakers included Black men from the South — for whom mill conditions and pay represented an improvement — adding racial tension to the conflict, according to the Encyclopedia Britannica. Unions at the time did not allow Black laborers to join.

In an unrelated incident, anarchist Alexander Berkman shot and stabbed Frick at his Downtown office on Fifth Avenue between Wood Street and McMasters Way on July 23, 1892. Berkman had no connection to Homestead or its union, but the failed assassination attempt decisively shifted public sentiment against the strikers.

In November, the strike officially crumbled with a union vote of 101 in favor of returning to work, 91 against, according to the Pittsburgh Post. Returning workers had to accept Carnegie’s pay cuts and 12-hour days, and more than 300 — according to Rivers of Steel — were blacklisted from the steel business, never to be employed in it again.

Organized labor collapsed throughout the industry. It did not recover for more than 40 years.

As recently as the 1980s, Squirrel Hill residents across the river from Homestead would sometimes awaken to find a layer of black grit on their cars and the smell of heavy industry in the air.

Odors weren’t the only plant emissions. The Clairton Works, the largest coke factory in the nation, has a long history of air quality violations, both federal and local. Some emissions have been linked to serious health problems including cancer, asthma and other breathing problems.

Today, Allegheny County posts daily updates on local air quality on its website and has air quality data online going back to at least 2016. Local environmental organizations like Group Against Smog and Pollution (GASP), which was formed in 1969, as well as the Breathe Project, PennEnvironment and Valley Clean Air Now, among others, have pushed companies for better compliance with environmental laws and regulations, and government for better enforcement.

Before the federal government began regulating pollution, virtually everyone denounced Pittsburgh’s sooty air and fouled water.

Even Carnegie in his autobiography called Pittsburgh “miserable,” saying, “if you washed [your] face and hands, they were as dirty as ever in an hour.”

Mon Valley mill towns in the late 1800s and early 1900s suffered from untreated sewage, unsanitary drinking water, unheated homes, smoke, toxic emissions and a generally dismal ambience made worse by Western Pennsylvania’s gloomy winters, as described in “Road to Rust: The Disintegration of the Steel Industry in Western Pennsylvania and Eastern Ohio” by Dale Richard Perelman.

Adding to the malaise, “these blue-collar businesses delivered prosperity to the merchants and the skilled craft workers, but also a heavy dose of crime, prostitution, gambling, alcohol, accidents and smoke,” Mr. Perelman wrote.

McKeesport, a city of 5.4 square miles, by 1906 had 69 saloons, he wrote. Braddock, just over half a square mile, had 65.

When the public desire to make air and water clean and safe spiked after World War II, leaders in Washington, D.C., eventually responded, creating the Environmental Protection Agency in 1970.

“As society has become more concerned about environmental quality, legislation has imposed higher standards on a basic industry in which, traditionally, pollution was seen as an unavoidable accompaniment of production,” author Kenneth Warren wrote in “Big Steel: The First Century of the United States Steel Corp., 1901-2001.”

“The United States has been in the forefront in requiring higher standards, and large, old-style steel plants have borne much of the cost.”

Carnegie exited the steel business in 1901 when he agreed to a merger with J.P. Morgan and Chicago’s Federal Steel Co., forming U.S. Steel, the first billion-dollar corporation.

At its formation, U.S. Steel produced 67% of all domestic steel, according to the National Iron & Steel Heritage Museum in Coatesville, Pa.

U.S. Steel quickly gobbled up other steel companies, including National Tube in McKeesport, “the largest pipe-producing plant in the world,” John P. Hoerr wrote in “And the Wolf Finally Came.”

In 1904, U.S. Steel bought the Clairton Works. When the company put more than 600 coke ovens there in 1918, Clairton became “the largest center in the world for this kind of coke production,” Hoerr wrote.

U.S. Steel was now huge.

It had mills in Ambridge, Sharon, Donora and New Castle plus many other places in and around Chicago and elsewhere. Rivals opened plants in Pittsburgh, Monessen, Aliquippa, Beaver, Johnstown, Wheeling, Weirton and Youngstown.

But they couldn’t touch U.S. Steel’s size and reach.

Aromas of pierogis and haluski filled the air last summer at the International Village in Renziehausen Park outside McKeesport as visitors enjoyed music and dance from Slovakia, Bulgaria, Croatia and Poland — vestiges of the huge influx of Eastern European immigrants who streamed into American mines and mills between 1880 and 1924.

The new arrivals a century ago didn’t speak English or know American customs. Fresh from the Austro-Hungarian and Russian empires on the eve of revolution, they brought ideas of communism and socialism to the shop floor, where they tended to fill the most unskilled jobs.

U.S. Steel and other companies tried to keep a lid on worker dissatisfaction. Sometimes their efforts provided workers with benefits, rudimentary safety measures and educational and recreational opportunities, according to “Homestead: The Story of a Steel Town.”

But the company also used informants to spy on workers, suppressed worker meetings, brought in strikebreakers and used its own police to enforce its will.

Tensions between workers skilled and unskilled, foreign-born and U.S.-born, and Black and white made unity difficult, and labor strikes failed.

All that changed during the Great Depression. With Democratic President Franklin D. Roosevelt in office and the country growing more desperate from seven years of economic hardship, U.S. Steel in a historic development agreed in 1937 to recognize the forerunner of the United Steelworkers union as the collective bargaining representative of its employees, and agreed to a 40-hour work week, pay raises and overtime pay.

Decades of rising pay, better benefits and safer working conditions followed, as did corporate expansion, notably the Irvin Works in 1938.

By 1973, in addition to McKeesport (the Christy Park and the National works), Braddock, Clairton, Duquesne, Homestead and West Mifflin, U.S. Steel listed steel and related facilities at Vandergrift, Dravosburg, Ellwood City, Rankin, Ambridge and McKees Rocks plus elsewhere in Pennsylvania and nine other states.

But the seeds of industry decline had already taken root.

McKeesport’s main street, Fifth Avenue, is now a ghost town of shuttered storefronts, empty lots and decaying buildings.

Braddock’s Braddock Avenue shows a few signs of life — a sprinkling of new construction, murals and businesses — with gaping holes that indicate where buildings once stood.

Duquesne has so little money, it had to close its storied high school in 2007. Ninety-three percent of the Duquesne school district’s 439 students were “economically disadvantaged” in 2024, according to a Post-Gazette article.

Homestead bustles at the riverbank where The Waterfront shopping complex stands, but the old main street of Eighth Avenue crumbles one block south, minimally touched by the nearby prosperity. The most visible remnant of the once mighty Homestead Works is a line of towering mill chimneys preserved at one end of the shopping complex.

Clairton retains well-kept homes and tidy lawns in spite of its many long-decrepit and empty storefronts. The coke plant puffs proudly in the distance.

The Mon Valley Works once powered all of these towns.

Edgar Thomson in Braddock at its height had some 20,000 workers; Homestead another 20,000; National Tube in McKeesport between 6,000 and 9,000; 4,000 at the Duquesne Works; 7,200 in Clairton; and 4,000 at the Irvin Works.

Their steel went into the Empire State Building, the Sears Tower (now the Willis Tower) in Chicago, the U.S. Steel Building, the United Nations building in New York City, the New Orleans Superdome, St. Louis’ Gateway Arch, part of NASA’s Kennedy Space Station in Florida and many bridges, including Pittsburgh’s “Three Sisters,” the Chesapeake Bay Bridge, the San Francisco-Oakland Bay Bridge and the Tappan Zee, Verrazano Narrows and Henry Hudson bridges in New York City.

An ecosystem grew up around each of these towns, with manufacturers that relied on steel standing nearby and main streets full of mom-and-pop businesses — “fruit stands, butcher shops, delis, clothing and furniture stores, five and dimes, car dealers, whorehouses and just about anything you wanted or needed on your way to work,” as Mr. Stout put it in his book.

“These were destinations,” said Anne Madarasz, chief historian at the Heinz History Center.

Homestead’s Eighth Avenue, the main street, “was like a little Broadway” in the 1950s, the late Stephen Simko, who rose from worker to supervisor in the Homestead Works and later became borough mayor, told author William Serrin.

“You could go there at 3 o’clock in the morning, and it would be full. …People were loaded into the ice cream stores, the saloons. … Money was no problem. … Everybody had cars, everybody was doing everything, buying everything.

“Oh, Christ, on payday — payday and the day after — the bars were going and there was music all over the place, loud so you could hear it outside. … There was gambling, prostitution. It was one of them real towns.”

The work created tight bonds. “When you go work in a steel mill … you have a new family,” Mr. Stout said in an interview at a South Hills cafe. “And your family, whether you liked it or not, whether you liked them or not … your lives depended on one another.”

Homestead’s population hit a high of 20,452 in 1920, McKeesport in 1940 with 55,355 people, Duquesne in 1930 with 21,396, Braddock in 1920 with 20,879, West Mifflin in 1970 at 28,070 and Clairton in 1950 with 19,652.

Today those towns’ total populations are often less than the number of people who once worked in their mills.

By the 1970s, those big mills lining the Monongahela River, once symbols of U.S. Steel’s size and dominance, came to characterize the company’s lack of agility.

After the devastation of World War II, foreign steelmaking lay in ruins.

But as foreign manufacturers built their industries from scratch, they passed U.S. Steel in efficiency, quality and cost.

U.S. Steel expanded its production in the 1950s, but used old open hearth technology, while Germany had invented the more efficient basic oxygen furnace, Hoerr wrote.

Even in the 1950s, “[a]rrogance and smugness [on the part of the steel industry] drove smaller users with specific technological requirements abroad, since large American steel manufacturers ignored their requirements,” Perelman wrote in “Road to Rust.”

Quality slipped. A saying developed, Serrin wrote in “Homestead: The Glory and Tragedy of an American Steel Town”: “As long as it is hard and gray, ship it.”

Domestic minimills, smaller and more efficient than traditional mills, cropped up in the 1960s, further eroding U.S Steel’s dominance. Minimills use mostly scrap metal rather than making steel from scratch.

“American steel had failed to make the essential investments to remain competitive and Pittsburgh had long since lost its role as an ideal location for making steel,” wrote Christopher Briem, an economist at the University of Pittsburgh's Center for Social and Urban Research, in an essay published earlier this year in Public Source.

Relations between the company and labor remained tense. Hoerr described U.S Steel management as controlling, opaque and lacking compassion.

Trouble came from the other side of the relationship as well. “The militant stance of American labor had become brazen” after a 1959 strike, Perelman wrote in “Road to Rust.”

A “byzantine” system of work rules made it “practically impossible to fire a worker,” Serrin wrote.

Additionally, “crippling” labor costs gave competitors an advantage, Perelman wrote. As early as 1959, American steelworkers were earning four times the pay of European steelworkers and seven times more than their Japanese counterparts, Warren wrote in “Big Steel.”

In 1963, the union contract stipulated 13 weeks of paid vacation for workers with more than five years of service, according to Serrin.

“I think everybody, including the hourly workers, the management, the higher-ups, became complacent,” one Homestead mill superintendent told Serrin. “They said, ‘We’re going to be here forever. We’re making money like there’s no tomorrow.’ ”

Tomorrow came in the 1970s.

Demand for steel dropped — the market for household appliances grew saturated and the oil crisis led carmakers to use lighter materials than steel to be more fuel efficient.

When a recession arrived in 1981, the American steel industry came crashing down.

On Thursday, May 24, 1984, U.S. Steel shut down its Dorothy Six furnace at the Duquesne Works for good.

Steelworkers wore black arm bands. “Taps” sounded on the mill’s public address system.

Bob Macey, then 35, held two bags containing everything from his company locker.

“This arm band symbolizes the death of a blast furnace, the death of the plant, the death of my job,” he told the Associated Press.

The Homestead Works shuttered in 1986.

“Steel is never coming back,” said Homestead Mayor Stephen Simko, a former supervisor at “The Big Shop,” Homestead’s prized Valley Machine Shop. “We made some fantastic things down there. We made almost all the armor plate for the U.S. Navy.”

One group of Homestead workers marked their last day on the job with a lunch of homemade kielbasa and sauerkraut, beer, hot dogs and watermelon, Serrin wrote.

Mr. Stout was there.

“It was a slow-motion holocaust,” he said of the gradual shutdown of the Homestead Works.

The last 22 workers at the National Tube Works in McKeesport bid the plant a final farewell with a keg of beer and a picnic in 1987. Two of the men sang an old Croatian tune.

“Ten years ago I would have bet anyone that this would never happen,” one of the workers told the Post-Gazette.

Nippon Steel’s purchase of U.S. Steel this year came after a battle played out on the national stage.

In 2023, Ohio-based rival Cleveland Cliffs made an unsolicited bid to buy the company. U.S. Steel said no, and sought competing bids, finally accepting one from Nippon, the world’s fourth-largest steel producer according to the Brussels-based nonprofit WorldSteel Association. U.S. Steel ranks 29th in steel production, with 14.1 million tons in 2024, WorldSteel statistics show.

The USW, representing about 11,000 workers at U.S. Steel plus many at Cleveland Cliffs, opposed the Nippon offer.

Then-President Joe Biden, Pa. Sen. John Fetterman, Gov. Josh Shapiro and presidential candidate Donald Trump also came out against the plan.

A national security review reached no conclusion, and Mr. Biden blocked the deal.

“There is credible evidence that leads me to believe that” if Nippon Steel and its related companies acquired U.S. Steel, they “might take action that threatens to impair the national security of the United States,” read part of President Biden’s Jan. 3 order against the proposal.

Officially, the USW remained wary of a foreign company owning U.S. Steel and watchful of Nippon’s “long history of committing unfair trade practices.”

“Our members know from decades of negotiating contracts: Trust nothing until you see it in writing,” the union said in a May 30 statement.

Unofficially, though, many Mon Valley workers rallied for the purchase.

“Without this deal with Nippon Steel, we will be the last generation to work here at this historic steel plant,” a third-generation steelworker from the Clairton plant told the Post-Gazette.

Clairton Mayor Richard Littanzi put it more succinctly:

If the deal didn’t go through, he said, “the Mon Valley is dead.”

After Mr. Biden lost the 2024 presidential election, the proposal went through another security review, this time with Trump appointees. The deal was approved with provisions: Nippon had to commit to invest in American plants, keep U.S. Steel headquartered in Pittsburgh, keep the majority of U.S. Steel’s board composed of U.S. citizens, and maintain production levels, according to Post-Gazette coverage.

The acquisition also gave the federal government a “golden share” in the merged company, an ownership stake that carries the power to override any effort to relocate the company, rename it, move its jobs outside the country, acquire rivals and other decisions involving closures, idling, trade, labor and sourcing.

The term golden share has been used internationally to mean giving a country’s government a preferential piece of ownership in a company that allows that government to have significant control over decisions that could affect national security. Governments don’t normally earn money or any kind of economic reward from golden shares.

With new safeguards and more money on the table, Mr. Shapiro praised the acquisition. Mr. Fetterman said the original deal was “a death sentence for Mon Valley steel,” and that now that Nippon had pledged more money, he would continue to support “the union way of life.”

The USW vowed to hold Nippon to its promises and criticized the golden share as giving Trump a “startling degree of personal power over the corporation.”

Today, the Mon Valley Works — Braddock, Clairton, West Mifflin — keep running, though with a much-reduced labor force that U.S. Steel estimates at about 3,000 people.

U.S. Steel Executive Vice President and Chief Financial Officer Kevin Lewis. (Courtesy of U.S. Steel)

Coal motors down the Monongahela River on barges to Clairton and leaves as coke on other barges bound for Braddock. There, the workers forge the coke with Minnesota iron and other materials to form steel slabs. These go by rail to West Mifflin, where the Irvin plant treats the steel and shapes it into coils for industrial use.

The Nippon acquisition “means a secure future for generations to come” in the Mon Valley, said U.S. Steel Executive Vice President and Chief Financial Officer Kevin Lewis.

He praised the new hot strip mill that will be installed in Braddock, replacing a 1938 one at the Irvin Works.

“I’m not confident we would have made that investment as a standalone company without a partnership with Nippon,” he said.

He characterized labor-management relations as “very constructive.”

“We have a lot of shared goals.”

On labor’s side, the mood is more tempered.

“We’re cautiously optimistic” about the Mon Valley’s future, Bernie Hall, director of the USW’s District 10, which covers Pennsylvania, said from his Forest Hills office. “Our immediate goals are holding Nippon Steel and U.S. Steel to the commitments they’ve made.”

The union’s bargaining agreement expires in August 2026, he said.

Laura Malt Schneiderman, lschneiderman@post-gazette.com

Correction, posted Dec. 19, 2025: An earlier version of this story misrepresented how many employees the United Steelworkers represents at U.S. Steel. The union represents about 11,000 U.S. Steel employees.

A steelworker breaks sand barrels as molten metal changes courses, Aug. 2, 1980.
(Carol Morton/The Pittsburgh Press)

Businesses pack Braddock, April 22, 1977.
(Lynn Johnston/The Pittsburgh Press)

The Homestead Works blows smoke as cars travel down what appears to be Eighth Avenue on Jan. 14, 1941.
(Wilbur Coffman/Post-Gazette)

Smoke billows from the Clairton Works on April 18, 1973.
(Post-Gazette archive)

Arzeno “The Stratosphere Man” Selden took this photo of the Edgar Thomson Works in 1948.
(The Pittsburgh Press ROTO Magazine)

Aaron Coates works in the basic oxygen process (BOP) shop control room, Sept. 16, 1980, in the Edgar Thomson Works, Braddock. (Carol Morton/The Pittsburgh Press)