Question

Germany's invasion of the Soviet Union was slowed largely because of

Answer 1

Answer:
the unforeseen necessity of invading Yugoslavia and Greece in April of that year.

Step-by-step explanation:

Hitler and his generals had originally scheduled the invasion of the U.S.S.R. for mid-May 1941, but the unforeseen necessity of invading Yugoslavia and Greece in April of that year forced them to postpone the Soviet campaign to late June.