The dog, Jackie, was a mutt owned by Tor Borg, a businessman from the Finnish city of Tampere. Borg's wife Josefine, a German citizen known for her anti-Nazi sentiments, dubbed the dog Hitler because of the strange way it raised its paw high in the air like Germans greeting the Fuehrer with a cry of "Heil Hitler!"
On January 29, 1941, German Vice Consul Willy Erkelenz in Helsinki wrote that "a witness, who does not want to be named, said ... he saw and heard how Borg's dog reacted to the command 'Hitler' by raising its paw."
Borg was ordered to the German embassy in Helsinki and questioned about his dog's unusual greeting habits.
He denied ever calling the dog by the German dictator's name, but admitted that his wife called the dog Hitler. He tried to play down the accusations, saying the paw-raising had only happened a few times in 1933 — shortly after Hitler came to power.
The German Foreign Office was ready to arrest Borg for insulting Hitler, but no one wanted to testify against the man. Link -via Metafilter