Ulrich Friedrich Wilhelm Joachim von Ribbentrop ( born Ulrich Friedrich Wilhelm Joachim Ribbentrop ) ( 30 April 1893 â `` 16 October 1946 ) was Foreign Minister of Germany from 1938 until 1945 . Ulrich Friedrich Wilhelm Joachim von Ribbentrop ( 30 April 1893 â `` 16 October 1946 ) was Foreign Minister of Germany from 1938 until 1945 .