There were two immediate effects.
1) Israel came into being as a democracy with a parliamentary style of governance.
2) The surrounding Arab Nations declared war on the nascent State of Israel, widening the contemporaneous Jewish-Arab Engagement into an international war (the Arab-Israeli War of 1948-9).
The Balfour Declaration is often seen as the initiation of the process leading to the establishment of the State of Israel. -
Prime Minister David Ben Gurion proclaimed the establishment of the State of Israel in Tel Aviv on 14 May 1948.
Israel.
Israel
Israel was declared a state immediately after the Civil War in Mandatory Palestine of 1947-1948. However, in the wider world, Israel's establishment required the events of World War II and the Holocaust to make clear the need for Israel and allow for its establishment with UNGA Resolution 181 (II).
The establishment of Israel resulted in the migration of hundreds of thousands of Jews.
720,000A+
The Soviet Union, the United States, and the worldwide Jewish community were the chief supporters of the right to establish a Jewish State and led the vote to establish Israel. The Arab States and Britain were chiefly opposed to establishment of a Jewish State. After 1953, Britain became a strong ally of Israel and the Soviet Union became one of Israel's chief antaognists.
Zionism is the belief that the Jews should have political self-sovereignty and is the patriotic sentiment behind the Establishment of the State of Israel. The existence and preservation of the State of Israel is probably the clearest example of Zionism.
Palestinian Arabs fled Palestine after the establishment of Israel.
The partition plan to create the state of Israel was approved by a vote of 33 to 13, with 10 abstentions.
A lot of things indirectly led to the establishment of the State of Israel. Probably the most commonly referenced is the Holocaust, because the Holocaust made clear the extent of animosity held against the Jews and their need for an independent nation to defend their interests.