History
Modern-day Israel was founded in 1948 with the support of the UN, and it was recognized as a natural part of the international community. The right of the country to exist within safe and recognized borders are enshrined in international public law.
The independence of Israel in 1948 was part of a long chain of events. Ancient-history Israel was part of one of the oldest nations, and most modern states today are actually younger than modern-state Israel. Throughout history, many have claimed the area sometimes referred to as Palestine. Israel is however the only nation-state to have ever existed there. When modern-day Israel was founded, it was mainly made up of the areas which already had a Jewish administration. The Holocaust of the European Jews illustrated the importance of a Jewish state, but the actual process of founding the state had in practise started earlier.
History 1917 to 1948
After WWI the League of Nations establish a Mandate System, which was supposed to let the Mandates transform into independence after a 'period of maturing'. Great Britain was put to administer the Palestine Mandate (also known as the 'Mandate for Palestine'), including the area of present-day Jordan, the West Bank (Judea and Samaria), Israel, the Gaza Strip and the western part of what later was to become Iraq. The British had conquered these areas during the end of the First World War. Before the conquest, the British had negotiated with both Jewish as well as Arab representatives of the area and promised future independence in exchange for support in the struggle against the Ottoman Empire - that is, the Turks. In 1917, the Jewish people were promised a national home in Palestine in the Balfour Declaration; this text was later integrated into the League of Nations instructions for the Palestine Mandate. In 1922, Great Britain decided to break up the Palestine Mandate into two parts; the area east of the River of Jordan - 75% of the area - thus became the Arab Transjordan (which later changed its name into Jordan).
After the WWII, the United Nations had to deal with the issues of the various Mandates. The British failed to solve the antagonism in the area that was now left of Palestine (the area west of the River Jordan) - thus, the United Nations was given task of splitting the area yet another time. The UN (UNSCOP) suggested in its final partition plan of 1947 that a Jewish and an Arab state would be established (in addition to Transjordan). Jerusalem would be put under international administration and become a free-trade zone, open for all and everyone. The Jews reluctantly accepted the plan, while the Arabs rejected any partition of western Palestine.
The 1949 borders - the War of Independence
The British experienced ever-increasing problems with administering the region, and neither liked the partition plan, nor the UN call for them to leave the area. Instead, the British chose to leave its Mandate prematurely, before the time period set by the UN resolution. When the British left the area, there was a legal vacuum, where the Jewish authorities controlled a small area than prescribed by the partition plan; at the same time, the other areas came under control of the neighbouring states. The result was the Israel declared itself independent, while sex Arab states attacked the new nation. Israel chose not to define the borders of its state.
During the war of independence, both Israel and its neighbouring Arab states conquered territories from areas with legal vacuum. In 1949, the hostilities ended when a cease-fire agreement came into effect. These agreements did not stipulate the borders, but called for future peace agreements to decide where the exact borders would be drawn. Also the United Nations expressed that the borders would be set by the parties in future agreements.
The 1967 borders - the Six Day War.
The period after the cease-fire agreement was characterised by constant paramilitary attacks and terror attacks on Israel from the areas (the West Bank and the Gaza Strip) recently conquered by the neighbouring states. These attacks took place with the explicit goal of eradicating the Jewish state. Israel was presented official warnings in the UN and directly to the Arab League, asking for the attacks to stop. After masses of Arab troops gathered, a call for war by Egypt and an Egypt-enforced a blockade of Israeli shipping, Israel hit in self-defence against Egypt. In response, Jordan and Syria attack Israel. In the following Six Day War, Israel conquers territory from Jordan (East Jerusalem and the West Bank), Egypt (the Sinai Desert and Gaza) and Syria (the Golan Heights). Parts of these territories, Israel has used to trade land for peace, while other areas still are subject to negotiations
Time axis
Biblical time  1300-1200 BC: Israelites settle in the Land of Israel 
Foreign domination  313-636 AD: Byzant rule.  1897: The First Zionist congress, called for by Theodor Herzel, is held in Basel, Switzerland. This marks the foundation of the Zionist organisation. |
The British Mandate The State of Israel  1949: Cease-fire agreements were signed with Egypt, Jordan, Syria and Lebanon. Israel gets accepted as the 59th UN member state.  1968-1970: The Egyptian War of Attrition against Israel. |