In his memoir Conversations With Stalin, apparatchik-turned-dissident Milovan Djilas reports an awkward interaction with a Soviet handler during a 1948 trip to Leningrad. “In no Party in Eastern Europe,” the handler intimated, “is there such a closely watched foursome as yours.” The party was the Communist Party of Yugoslavia (CPY), and the foursome was Djilas, Edvard Kardelj, Aleksandar Ranković, and Tito. These were the CPY’s four most powerful members in the late 1940s, but Tito — the nom de guerre of Josip Broz — stood above the rest as the unquestioned leader of Communist Yugoslavia.

Why did the Soviets keep such a close eye on their ostensible comrades in the Balkans? After all, the Yugoslavs were, as the Marxist writer Isaac Deutscher describes them in his biography of Stalin, “up till 1948, considered to be the most dogmatic and fanatical of all European Stalinists.” After they took power in 1945, Tito and his comrades quickly and diligently constructed a new state along impeccably Soviet lines. According to historian Ivo Banac,

The Yugoslavs were not only the first to abolish monarchy in Eastern Europe, they were also the first to adopt a Soviet-style constitution (January 1946), the first to institute legal procedures against church dignitaries of episcopal rank (the trial of Archbishop Alojzije Stepinac in October 1946) and the “opposition within the united front,” the first to use rigged trials against their own wayward members (the Dachau trials of April and August of 1948 and July 1949), the first to introduce Soviet-style planning (First Five-Year Plan of April 1947 with the highest rate of state investment of 27 percent of GNP in Eastern Europe) and the first to establish collective farms (1,318 by the end of 1948).