Guernica
The Battle Britain
In 1914 the German army invaded Belgium on it's way to France. During the Schrieffer plan Germany thought that going through Belgium was going to be easy and that Britain was going to remain neutral if Germany attacked Belgium.
Problems with logistics and communications contributed to the long period of stalemate during World War I. The stalemate happened after the British forces attacked and captured Neuve Chapelle in the Artois region.
The Soviet Union ... plus assorted individual socialists. Britain
AnswerPoland attacked the Nazis first during World War 2.
Guernica
Germany attacked Britain during the Battle of Britain.
No country attacked Germany in World War 2 (which you seem to be confusing with the Holocaust). Germany was the aggressor.
Sweden remained neutral, but a supporter of Germany during WW2. Sweden was not attacked or occupied by Germany.
There were quite a few. But you're probably thinking of Guernica, which was bombed by the German airforce, in an attack which inspired a painting by Picasso.
Germany invaded Poland.
Germany attacked several major cities in the Soviet Union during World War II. Among the cities attacked were Moscow, Stalingrad, and Leningrad.
Germany supported Franco during the Spanish Civil War of 1936, and tested their weapons during that war.
germany
The Battle Britain
general Andrew Jackson
Poland, Holland, Belgium, France, Denmark, Norway, Luxembourg, Yugoslavia, Greece, and the Soviet Union were attacked by German armies and air forces. Also, Great Britain and Malta were heavily attacked by Germany from the air, and at sea the ships of many Allied nations were attacked by the Germany Navy.