What was the largest genocide in human history?

The Nazi Holocaust of the Jews.

The biggest genocide was done by the Europeans against the Native Americans wiping out more then 100 million people in the most barbaric ways. First here is def. of Genocide is defined as "the deliberate and systematic destruction, in whole or in part, of an ethnic, racial, religious, or national group",

Instead of calling people names you should do some research. The introduction of European disease caused the "native tribes" of the America's to decline more than any other event.

The second biggest was by Chairmen Mao in the 1950's when China became a Communist nation. nearly 30 million according to china's own information.

And the 3rd biggest genocide was by Joseph Stalin who killed some 23 million of his own people including 7 million Ukrainians who were starved to death.

In conclusion Stalin and the Russian Pogroms is the "winner". Because many of the dead in China were not executed but died from starvation and after affects of the transition. I could listen to an argument that China was "winner". To site European's vs. unnamed native tribes is classic case of not understanding the question or history.