Brush up on your Marx, fish out your tattered Communist Manifesto, and practice singing the "Internationale," preferably in multiple languages: May Day is just around the corner! For those who've forgotten this milestone, May 1 is the international proletarian holiday, the day when tanks used to parade down the streets of Moscow, les syndicalistes rioted in Paris, and students threw bottles at police in Warsaw. Though the United States celebrates Labor Day instead—a boring, noncommunist alternative, albeit a useful reminder that it's time to pack the beach towels away—you can still join in the May Day fun. Paradoxically, there has never been a better time to read up on the history of the communist movement: Now that most Communist regimes have collapsed or surrendered, the archives are open, and new books are appearing all the time.
Start out, of course, by ignoring the latter-day Marxists and reading Marx: The first 10 volumes of the complete works of Marx and Engels are now available and searchable online. If you really do just want the Communist Manifesto (recommended for those with limited tolerance for turgid prose), it's available here in the original Progress Publishers translation.
Those who want to know how the communist theory worked in practice should then turn to Robert Service's Comrades, one of the best of many recent accounts of how the movement grew, spread, and briefly captivated half the world before collapsing in 1989. If you want more blood and gore, read The Black Book of Communism, compiled by French ex-Trotskyites. Service's book is better on the Comintern, Titoism, and the Sino-Soviet split. The Black Book's authors are better on torture, concentration camps, and mass murder. Take your pick or read them both.
Once you've got the surveys under your belt, you can turn to Yale University Press' Annals of Communism series, a unique publishing venture designed to make use of Soviet archives. Whether you want Andrei Sakharov's personal files, Stalin's correspondence with Molotov, or documents explaining the Katyn massacre, they're all available in beautifully edited and annotated translations. Don't miss John Haynes and Harvey Klehr's history of the American Communist Party (also a Yale book, also based on Soviet archives), either.
And this is just the beginning. If nothing else, the past decade has proved that open archives really do lead to better history books, whether the scholarly kind, like Harvard historian Terry Martin's Affirmative Action Empire, a history of Soviet nationality policy, or the popular kind, like Simon Sebag Montefiore's Stalin: The Court of the Red Tsar, a juicy, gossipy account of Stalin's inner circle. Thanks to archives, the history of World War II is also being rewritten—see Antony Beevor's Stalingrad and Berlin: The Downfall—as are other chunks of 20th-century history, such as the Spanish Civil War.
Still, there's nothing like an eyewitness. So if, having made your way through all of these history books, you still feel something lacking, try to track down an old copy of Utopias Elsewhere, British writer Anthony Daniels' vicious 1991 account of life in some of the weirder Marxist regimes. Daniels makes all of these places sound strange, sad, and funny, all at the same time. Which they were—or are, in the case of North Korea and Cuba—as we so easily, too easily, forget.