Final answer:
Jewish Zionists in Palestine were primarily financed and armed by the Haganah, a defense force created by the settlers, and they received significant support from the United States and Britain post-World War II, ultimately leading to the establishment and defense of the State of Israel.
Step-by-step explanation:
The question regarding who was financing and arming Jewish Zionists in Palestine during and after World War II encompasses several entities. Prior to the British relinquishing their mandate over Palestine to the United Nations, Zionist settlers had formed the Haganah, a mutual defense force, which turned to sabotage against the British and organized illicit arms shipments to prepare for future conflicts. Post-war support largely came from the United States and Britain, who, influenced by the atrocities of the Holocaust and a sense of guilt for not having done enough for Jewish refugees during the war, viewed the creation of a Jewish homeland with sympathy.
After World War II, as Jewish survivors of the Holocaust sought refuge in Palestine, tensions with Palestinian Arabs increased. The British government struggled to find a plan that would appease both sides, and the United Nations was called upon to resolve the dispute. In 1947, the UN proposed the partition of Palestine into separate Jewish and Arab states, a plan that neither side fully accepted. After declaring independence in 1948, Israel received additional support from the US and Britain, which enabled it to defend itself and even extend its borders in the subsequent conflict with its Arab neighbors.