From 1920-1948, the British Government administered present-day Israel and Palestine as Mandatory Palestine. Facing sectarian violence from both Jewish settlers and Palestinian Arab peoples, the British Government issued the White Paper of 1939.

By the time the White Paper was issued, the demographic transformation of Mandatory Palestine was already striking. The 1922 census recorded a population of roughly 757,000, of whom only 11% were Jewish; by 1936, that share had nearly tripled to almost 30%, and the White Paper itself acknowledged that the Jewish population had “risen to some 450,000” — approaching one-third of the total — by 1939.

This shift was driven almost entirely by immigration: more than 250,000 Jewish immigrants arrived in the single decade between 1929 and 1939 alone. To appreciate the scale, consider that this was happening in a territory roughly the size of New Jersey — one of America’s smallest states — while the United States itself, a nation a thousand times larger, admitted a yearly average of only about 70,000 legal immigrants throughout the entire 1930s after its own restrictive quota laws took effect. Palestine had, in a very real sense, already absorbed an extraordinary demographic transformation before the White Paper sought to slow it further. This document capped Jewish immigration to Mandatory Palestine at 75,000 over five years.

During World War II, this policy had severe humanitarian consequences: tens of thousands of Jewish refugees fleeing Nazi persecution for Palestine were prevented from entering by the British. In addition, organized illegal immigration, known as Aliyah Bet, brought refugees on clandestine ships; the British intercepted many of these voyages. This period is among the morally complex of British Mandatory rule.