After the first Brazilian constitution in 1824 that granted freedom of religion, Jews began to arrive gradually in Brazil. Many Moroccan Jews arrived in the 19th century, principally because of the rubber boom, settling on the Amazon, where their mixed-race descendants continue to live. Waves of Jewish immigration occurred first by Russian and Polish Jews escaping pogroms and the Russian Revolution, and then during the 1930s during the rise of Nazis in Europe.