This is a very sad book, the story of thousands of Americans who, during the Depression, lured by sham Soviet propaganda and pro-Soviet falsehoods spread by the likes of George Bernard Shaw and the corrupt New York Times Moscow correspondent, Walter Duranty, migrated to the USSR in search of jobs and a role in the “building of socialism.” It was, in the words of the author, “the least heralded migration in American history” and a period when “for the first time in her short history more people were leaving the United States than were arriving.” Most of these expatriates, not intellectuals but simple working men, were quickly disenchanted and wanted to return home, only to find that Moscow considered them Soviet citizens and barred them from leaving. Ignored by the American government, many of them ended in the gulag. In Tim Tzouliadis’s “The Forsaken” (Penguin Press, 436 pages, $29.95), their dismal story is told with great skill and indignation usually missing from Western accounts of communist Russia.

They came to Russia full of enthusiasm, bringing with them baseball and jazz, and eager to acclimatize. Russians found it difficult to believe the Americans’ tales of woe when they saw their clothes, luxurious by Russian standards. And the migrants were themselves quite unprepared for the poverty and lawlessness which characterized life under Stalin, and in many if not most cases decided to leave. They soon learned, however, that when they surrendered their American passports upon stepping on Soviet soil (passports which were then used by Soviet agents in America), they had become, automatically, Soviet citizens. Protests and appeals to the American authorities qualified the émigrés in Moscow’s eyes as troublemakers and led to their arrests, followed by confinement in concentration camps.

Stalin, whose paranoia grew to the point where he confessed he could not even trust himself, had no use for these foreigners. This was for two reasons. One was that he feared they would spread discontent among Soviet citizens. The other was that he feared they would demand repatriation and, on returning home, enlighten Americans about the dreadful conditions of life in the USSR. So he ordered them to be treated as Soviet citizens, accused of “espionage” and isolated in the Gulag from which few were expected to emerge alive.

Mr. Tzouliadis, a Greek native raised in England and currently a documentary filmmaker and television journalist, cites example after example of the U.S. State Department and its consular officials in Moscow ignoring appeals for assistance from these forlorn men and women. Sympathize as one may with their plight, I think he is somewhat unfair to the American authorities in stressing their failure to provide “the forsaken” with assistance. After all, they were not abducted, but went to the USSR voluntarily, and in most cases the American authorities found it impossible to determine whether they freely gave up their American citizenship or were robbed of it.

The scope of this admirable work is broader than the title indicates. The American expatriates dissolved in Soviet society, especially after they were incarcerated, becoming nonpersons, and their stories, too, became tied up with the broader Soviet one.

Much of the book deals with American-Soviet relations during the 1930s and 1940s. We are given examples of the incredible naïveté of Franklin Roosevelt, who lacked even elementary knowledge of the Communist regime: He is quoted as asking, “How could Stalin afford to buy all these factories?” There are vignettes of the no less naïve vice president, Henry Wallace, who visited the concentration camp at Magadan and found nothing amiss, as well as of the despicable American ambassador to Moscow, the multimillionaire Joseph Davies, who liked everything in the Soviet Union and even took Stalin’s show trials at face value. These public figures eclipse the poor devils who had themselves migrated to the Soviet Union — and who flit in and out of the pages of this book, faceless and nameless.

The only expatriate to emerge as a distinct personality is one Thomas Sgovio, an aspiring artist from Buffalo and the son of an American communist, who miraculously survived years in the Kolyma camp and on his return to America published his memoirs.

Sgovio arrived in Moscow in 1935. At first all went well, as he joined a chorus and worked on his drawing and painting. But in 1938, in the midst of Stalin’s terror, during which his father and many of his friends were arrested, Sgovio paid a visit to the American embassy to seek help. Upon leaving, he was immediately arrested. He was interrogated and condemned to five years in the notorious Kolyma camp, a place with the coldest recorded temperatures on earth. When his term lapsed, he was kept imprisoned: Of the 25 years he lived in the Soviet Union, 16 were spent in prison or concentration camp. Finally in 1960 he was allowed to return to America. His tale of misery and helplessness were repeated thousands of times by others less fortunate, among them his father, who spent 10 years doing hard labor, only to die shortly after being released.

The horror that was Stalinist Russia is still incomprehensible to many Americans, even to many of those who study the USSR professionally. Reading this book is certain to open their eyes.

Mr. Pipes is Baird professor of history, emeritus, at Harvard University and the author, most recently, of “Russian Conservatism and Its Critics.”