They thought this was their chance.

May 10, 1969, marked 100 years since the golden spike was hammered in at Promontory, Utah, signifying the completion of America’s first transcontinental railroad — a monumental engineering feat that linked together the nation's coasts.

A ceremony commemorating the anniversary drew a crowd of around 20,000. Among the attendees were Philip P. Choy, president of the San Francisco-based Chinese Historical Society of America, and Thomas W. Chinn, one of its founders.

Centennial officials had agreed to set aside five minutes of the ceremony for the society to pay homage to the Chinese workers who had helped build the railroad, but whose contributions had been largely glossed over in history. Choy, Chinn and the others gathered at Promontory that day had hoped this would be the moment when the more than 10,000 Chinese who labored for the Central Pacific Railroad finally got their due.

They didn’t.

“Who else but Americans could drill 10 tunnels in mountains 30 feet deep in snow?” then-Transportation Secretary John A. Volpe said in his speech, according to a May 12, 1969, San Francisco Chronicle article.

“Who else but Americans could chisel through miles of solid granite? Who else but Americans could have laid 10 miles of track in 12 hours?”

Volpe’s remarks referenced some of the backbreaking and deadly work done on the Central Pacific by a labor force that was almost 90 percent Chinese, many of them migrants from China, ineligible to become U.S. naturalized citizens under federal law.

But the ceremony featured nothing more than a “passing mention of the Chinese.” The five minutes promised to the society never happened.

Choy and Chinn were incensed.

“Short of cussing at those people ... I was beside myself,” Choy, who passed away in 2017, recalled during a 2013 interview.

This May, for the 150th anniversary, descendants of the Chinese railroad laborers and other advocates have been working hard to ensure history does not repeat itself. Among the events planned around the sesquicentennial is the 2019 Golden Spike Conference, organized by the Chinese Railroad Workers Descendants Association, which will feature workshops, lectures, tours and a musical by Jason Ma entitled “Gold Mountain.”

“It is the best opportunity I will have in my lifetime to have this story shared, to have it understood and appreciated by people outside our community,” said Michael Kwan, the association’s president, whose great-great grandfather worked for the Central Pacific.

Leaders of the Central Pacific and Union Pacific Railroad lines meet and shake hands in this iconic photograph taken by Andrew J. Russell on May 10, 1869. Previous scholars and historians believed that there were no Chinese workers in this photo, but Stanford researchers identified two of them in the crowd. Stanford Historical Photograph Collection / Stanford University Libraries

AN EXPERIMENT YIELDS SUCCESS

The Central Pacific broke ground on the first transcontinental railroad Jan. 8, 1863, and built east from Sacramento. The Union Pacific Railroad pushed west from Council Bluffs, Iowa (bordering Omaha), where their rails joined existing eastern lines. Acts of Congress provided both companies with land grants and financing.

The first transcontinental railroad became a boon to the economy of a nation recovering from a civil war, shaving significant travel time across the continent from several months to about a week. Produce and natural resources were among the things that could now be moved more quickly and cheaply from coast to coast.

It also generated tremendous wealth for railroad tycoons such as Leland Stanford, a former California governor who ran under an anti-Chinese immigrant platform. Stanford also served as president of the Central Pacific and later established the university that bears his name.

To grow its workforce, the Central Pacific took out an advertisement in January 1865 seeking 5,000 railroad laborers, but only a few hundred whites responded, according to “The Chinese and the Iron Road: Building the Transcontinental Railroad,” a book scheduled for release in April and edited by Gordon H. Chang and Shelley Fisher Fishkin, co-directors of the Chinese Railroad Workers in North America Project at Stanford University.

Many whites who took the jobs did so for only a time, reluctant to shoulder the demanding and hazardous work expected of them. Eventually, they headed to the Nevada silver mines for better wages and the prospect of striking it rich, Hilton Obenzinger, the project’s associate director, said.

Chinese workers near an opening of the Summit Tunnel of the Central Pacific Road. Alfred A. Hart Photographs, 1862-1869 / Department of Special Collections, Stanford University Libraries

Facing a labor shortage, the railroad may have turned to recruiting Chinese at the suggestion of Central Pacific construction contractor Charles Crocker’s brother, E.B., a California Supreme Court justice and an attorney for the company. The Chinese had earlier worked on other California railroads as well as the Central Pacific in small numbers, according to the project.

But the plan hit opposition amid anti-Chinese sentiment that stemmed from the California Gold Rush. Among those initially against it was the Central Pacific construction supervisor, James H. Strobridge.

“He didn’t think they were strong enough,” Obenzinger told NBC News in a 2017 interview.

Strobridge also worried that the whites wouldn’t labor alongside the Chinese, who he thought lacked the brainpower to perform the work as well.

Eventually, he yielded and in 1865 the Central Pacific tested out 50 Chinese laborers. They were among the 50,000 to 60,000 Chinese living in California who arrived in the early 1850s to work in mining and other sectors of the American West, according to the project. They hailed from Sacramento, San Francisco and the gold-mining towns of the Sierra Nevada.

The success of the experiment led the Central Pacific to hire additional Chinese workers, but the Chinese labor pool in California soon ran out. So the company arranged with labor contractors to bring workers directly from China, mostly from Guangdong province in the south.

A camp of Chinese workers near Brown's Station of the Central Pacific Railroad. Alfred A. Hart Photographs, 1862-1869 / Department of Special Collections, Stanford University Libraries

At the time, it was a region enmeshed in political and social turmoil, but residents there often had contact with foreigners and were less fearful of taking long ocean voyages, making them good recruits, according to Fishkin.

“And particularly for sons who were not the first sons in the families, it often made more sense to try to seek your fortune abroad,” Fishkin added.

By the end of July 1865, boatloads of Chinese were arriving in San Francisco. Less than two years later, almost 90 percent of the Central Pacific workforce was Chinese; the rest were of European-American descent, mostly Irish. At its highest point, between 10,000 and 15,000 Chinese were working on the Central Pacific, with perhaps as many as 20,000 in total over time.

The Union Pacific, by contrast, had no Chinese laborers during the construction of the first transcontinental railroad. They instead relied on Civil War veterans and East Coast immigrants, among others, according to Chang.

THE LIVES THEY LIVED

“The Chinese and the Iron Road: Building the Transcontinental Railroad” and Chang’s separate book “Ghosts of Gold Mountain: The Epic Story of the Chinese Who Built the Transcontinental Railroad,” which is scheduled to be released in May, both describe the Chinese taking on some of the most dangerous, most exhausting assignments for less pay (and worse treatment) than their Euro-American counterparts.

Often toiling in extreme weather, they cleared obstructions, moved earth, bored tunnels and built retaining walls — work done virtually all by hand. They became experts in drayage, masonry, carpentry and track laying. Sometimes they were lowered off cliffs to plant explosive charges when blasting was necessary, knowing that once the fuse was lit the difference between life and death hinged on how fast they were brought back up.

But it wasn’t just the blasting that was dangerous.

“There were occasions when avalanches buried workers in snow and they weren’t found until the snow melted the following spring,” Fishkin said.

Workers blast a 60-foot-deep cut above Alta, California. Alfred A. Hart Photographs, 1862-1869 / Department of Special Collections, Stanford University Libraries

Since records of worker deaths weren’t kept, Stanford scholars don’t know precisely how many Chinese died building the railroad. They estimate there were hundreds, possibly more than a thousand.

Though they have discovered evidence that many workers were able to read and write in Chinese, Stanford researchers have found no letters or journals from them, perhaps because they were destroyed or not preserved during the ensuing social upheaval in China.

Despite this, the Chinese Railroad Workers Project has been able to glean insight into aspects of the laborers’ lives through their research.

They know, for instance, that the Chinese boiled water for tea, which helped stave off dysentery and other waterborne illnesses. They also know the men set up camps along the worksites, didn’t imbibe too much alcohol, worked well together, and sent money back to their families in China.

They even staged a strike in June 1867 demanding pay equal to whites, shorter workdays, and better working conditions, an action that helped counter the image that the Chinese were docile and wouldn’t fight for their rights.

From tunneling through solid granite to laying down 10 miles of track in a day, the Chinese workers proved their mettle time and again.

Even Leland Stanford, whose anti-Chinese views were central to his gubernatorial campaign, changed his tune.

“He comes to have open respect for the abilities, the work ethic, the talents and the hard work, the industriousness of the Chinese,” Chang said.

But at times Stanford, who was later elected to the U.S. Senate, still resurrected certain anti-Chinese rhetoric when running for or in office, Chang noted.

“Stanford became one of the wealthiest men in the world because of their labor,” he said. “But there’s also lots of evidence to show that the Stanfords had an affection for many of the Chinese, especially in their employ. So it wasn’t just an exploitative relationship.”

A HISTORY ERASED, A HISTORY RECOVERED

After completing the first transcontinental railroad in 1869, Chinese laborers fanned out across the United States to work on at least 71 other rail lines, according to Fishkin.

This came amid rising anti-Chinese sentiment and violence in the U.S., as whites blamed the Chinese for squeezing them out of jobs by accepting work at lower wages.

Owing to white hostility, tens of thousands of Chinese were forced to leave the U.S. by 1882, according to “The Chinese and the Iron Road.” That same year, Congress responded by passing the Chinese Exclusion Act, the first and only major federal law to explicitly suspend immigration for a specific nationality. It wasn’t repealed until 1943.

It is the best opportunity I will have in my lifetime to have this story shared, to have it understood and appreciated by people outside our community. Michael Kwan

Almost a quarter of a century later, in 1969, amid the backdrop of the civil rights movement, Choy and Chinn found themselves at Promontory Point, Utah, waiting for a moment that never came.

Since that day, advocates have continued working toward giving Chinese railroad laborers the recognition they deserve, in an effort to recover a period of history that connects China and the U.S.

In 2014, the U.S. Department of Labor inducted Chinese railroad workers into its Hall of Honor. Asian Americans and Pacific Islanders elected to Congress in record numbers are among supporters of a House resolution to recognize the workers and their contributions. And a commemorative postage stamp in their honor has been proposed as well.

There’s also the Chinese Railroad Workers Memorial Project, which has raised at least a quarter of a million dollars for a monument, and the Chinese Railroad Workers Descendants Association, whose members visit Utah schools to teach kids about the Chinese laborers.

Even artists, photographers, journalists and academics from China, as well as scholars from Taiwan and those with Stanford’s Chinese Railroad Workers Project, have immersed themselves in the topic.

“We want to make sure that this doesn’t end on May 10th,” Kwan, the descendants association president, said.

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