At the 1912 International Congress of Mathematicians Landau listed four problems in number theory about primes that he said were particularly hard using current mathematical methods.

Landau and his family emigrated to Mandatory Palestine in 1927 and he began teaching at the Hebrew University.

In addition, Landau became a pawn in a struggle for control of the university between Magnes and Chaim Weizmann and Albert Einstein.

Magnes suggested that Landau be appointed Rector of the university, but Einstein and Weizmann supported Selig Brodetsky.

Landau was disgusted by the dispute and decided to return to Göttingen, remaining there until he was forced out by the Nazi regime after the Machtergreifung in 1933, in a boycott organized by Oswald Teichmüller.