The worst was in the ruins of Warsaw, or the fields of Treblinka, or in the marshes of Belarus, or the pits of Babi Yar

The American and British soldiers who liberated the dying inmates from camps in Germany believed that they had discovered the horrors of Nazism. The images their photographers and cameramen captured of the corpses and living skeletons at Bergen-Belsen and Buchenwald seemed to convey the worst crimes of Hitler. As the Jews and Poles of Warsaw knew, and as Vasily Grossman and the Red Army soldiers knew, this was far from the truth. The worst was in the ruins of Warsaw, or the fields of Treblinka, or in the marshes of Belarus, or the pits of Babi Yar.

T. Snyder, Bloodlands (2010), 311-2

There's more on this around 382f. He is very good on uncovering our historiographical bias on this.

This cannot be said of any other European country

A rough estimate of two million total mortal losses on the territory of present-day Belarus during the Second World War seems reasonable and conservative. More than a million other people fled the Germans, and another two million were deported as forced labour or removed from their original residence for another reason. Beginning in 1944, the Soviets deported a quarter million more people to Poland and tens of thousands more to the Gulag. By the end of the war, half the population of Belarus had either been killed or moved. This cannot be said of any other European country. 

T. Snyder, Bloodlands (2010), 251

Traditional empires had never done anything like this to Jews

Traditional empires had never done anything like this to Jews. On any given day in the second half of 1941, the Germans shot more Jews than had been killed in the entire history of the Russian Empire

T. Snyder, Bloodlands (2010), 227

Hitler, on the other hand, planned in advance to starve unwanted Soviet populations to death

As German planners saw matters, the collective farm should be used again to starve millions of people: in fact, this time, the intention was to kill tens of millions. Collectivization had brought starvation to Soviet Ukraine, first as an unintended consequence of inefficiencies and unrealistic grain targets, and then as an intended consequence of the vengeful extractions of late 1932 and early 1933. Hitler, on the other hand, planned in advance  to starve unwanted Soviet populations to death.... This was the Hunger Plan, as formulated by 23 May 1941: during and after the war on the USSR, the Germans intended to feed German soldiers and German (and west European) civilians by starving the Soviet citizens they would conquer, especially in the big cities. 

T. Snyder, Bloodlands (2010), 162

There came a moment in Ukraine when there was little or no grain, and the only meat was human

Cannibalism is a taboo of literature as well as life, as communities seek to protect their dignity by suppressing the record of this desperate mode of survival . Ukrainians outside the Soviet Union, then and since, have treated cannibalism as a source of great shame, Yet while cannibalism in soviet Ukraine in 1933 says much about the Soviet system, it says nothing about Ukrainians as a people. With starvation will come cannibalism. There came a moment in Ukraine when there was little or no grain, and the only meat was human. ... In the villages smoke coming from a cottage chimney was a suspicious sign, since it tended to mean that cannibals were eating a kill or that families were roasting one of their members.

T. Snyder, Bloodlands (2010), 51