Prior to the Anschluss Jansa and his staff had developed a scenario for Austria's defence against a German attack. Chancellor of AustriaSchuschnigg was under considerable pressure from Germany, to include the demand to remove Jansa from his office. The Berchtesgaden agreement (February 12, 1938) stipulated in paragraph 8, that Jansa should be replaced with Franz Böhme. Jansa retired from the army on February 17, 1938.
His father, Emanuel Jansa, was an Oberst in the Austro-Hungarian Army; his mother was Anna von Meyer. He married Judith Reviczky von Revisnye, on April 8, 1919.