Which German (promoted as being Austrian) was the first actor to win two consecutive Academy Awards (Oscars)?

Luise Rainer (1910 - 2014) was a German-born actress who won two consecutive Academy Awards for Best Actress. She was the first person to win two acting Oscars in a row. She was promoted as Austrian for political reasons.

Fun fact: Rainer was at home with her husband, playwright Clifford Odets, on the night of the ceremony.
She was told of her win by phone, dressed quickly, and rushed out to collect her second Oscar. I guess there was no red carpet back then.

https://en.wikipedia.org/wiki/Luise_Rainer