Between 1929 and 1938, 250,000 Jews arrived in Palestine (Fifth Aliyah). 174,000 arrived between 1933 and 1936, after which the British increasingly prevented immigration, mostly due to the outbreak of the 1936-1939 Arab Revolt. Migrants were mainly from Germany and included professionals, doctors, lawyers and professors. German architects of the Bauhaus school made Tel-Aviv the world's only city with purely Bauhaus neighbourhoods and Palestine had the highest per-capita percentage of doctors in the world.