When did the fear of communism known as the red scare begin in the united states?

Around 1949. When the Axis Capitulated and lost the war, Europe was divided and one half became proxy states, part of the Warsaw Pact. This Large Buildup of Soviet Power caused the US to be Highly suspicious of Communists and communism, which seemed to only Seek power over the West. 

That really sucks, but i don't know who your leader is, and i don't want to write that much