As the title asks, if Hitler was born in Austria and wasn't a citizen from birth how was Hitler able to be elected Chancellor of Germany? Did the Weimar Republic not have laws like the United States that prohibits non-native born Germans to be elected as Chancellor?
Hitler obtained German Citizenship through the Bavarian Government. The Weimar Republic allowed any German citizen to run for any government office. During the rise of the Nazi party, Hitler himself never was in the Reichstag since he was not a German citizen and therefore he could not participate. In 1925, actually, Hitler renounced his Austrian Citizenship and essentially was a man with no country. He took refuge near the Bavarian-Austrian border incase customs came and tried to have him arrested for his fanaticism while within Germany.
He obtained German Citizenship just after the 1932 elections, and became the German Chancellor in 1933.
Source: The Rise and Fall of the Third Reich: Book One by William Shirer