First Arab-Israeli War , 15 May 1948
Arab opposition to an Israeli state began after the Balfour Declaration 1917, which supported the idea of a Jewish national homeland. In the 1920s there were anti-Zionist riots in Palestine, after the British mandate government allowed thousands of Jews to immigrate to Palestine from all over the world.
In 1936 an Arab revolt led to a British royal commission that recommended partition (approved by United Nations 1947), but rejected by the Arabs.
When it became clear that the British intended to leave by May 15, leaders of the Yishuv decided (as they claim) to implement that part of the partition plan calling for establishment of a Jewish state. In Tel Aviv on May 14 the Provisional State Council, formerly the National Council, "representing the Jewish people in Palestine and the World Zionist Movement," proclaimed the "establishment of the Jewish State in Palestine, to be called Medinat Israel (the State of Israel) … open to the immigration of Jews from all the countries of their dispersion."
On May 15 the armies of Egypt, Transjordan (now Jordan), Syria, Lebanon, and Iraq joined Palestinian and other Arab guerrillas who had been fighting Jewish forces since November 1947. The war now became an international conflict, the first Arab-Israeli War.
The Arabs failed to prevent establishment of a Jewish state, and the war ended with four UN-arranged armistice agreements between Israel and Egypt, Lebanon, Jordan, and Syria. The frontiers defined in the armistice agreements remained until they were altered by Israel's conquests during the Six-Day War in 1967.
"Battle of the Roads". The Arab League sponsored Arab Liberation Army, composed of Palestinian Arabs and Arabs from other Middle Eastern countries, attacked Jewish communities in Palestine, and Jewish traffic on major roads. The Arab forces mainly concentrated on major roadways in an attempt to cut off Jewish communities from each other. Arab forces at that time had engaged in sporadic and unorganized ambushes since the riots of December 1947, and began to make organized attempts to cut off the highway linking Tel Aviv with Jerusalem, the city's only supply route. The Arab Army cut off supplies and controlled several strategic vantage points overlooking the sole highway linking Tel Aviv to Jerusalem, enabling them to fire at convoys going to the city. By late March 1948, the vital road that connected Tel Aviv to western Jerusalem, where about 16% of all Jews in the Palestinian region lived, was cut off and under siege.
April 6-12, 1948 : Operation Nachshon. The Haganah decided to launch a major military counteroffensive to break the siege of Jerusalem. On 6 April the Haganah and its strike force, the Palmach, in an offensive to secure strategic points, took al-Qastal, an important roadside town 2 kilometers west of Deir Yassin. But intense fighting lasted for days more as control of that key village remained contested.
April 9, 1948 : Throughout the siege on Jerusalem, Jewish convoys tried to reach the city to alleviate the food shortage, which, by April, had become critical. On 9 April 1948, IZL-Lehi forces attacked Deir Yassin, as part of Operation Nachshon to break the siege of western Jerusalem. On Deir Yassin massacre, Irgun and Lehi members attack the Arab village of Deir Yassin, killing between 100 and 120 Arabs civilians.
May 15, 1948 : Lebanon, Syria, Iraq, Egypt, Transjordan, Holy War Army, Arab Liberation Army, and local Arabs attack the new Jewish state with the intent of destroying it. The resulting 1948 Arab-Israeli War lasts for 13 months. By the end of the war, about 700,000 Palestinian Arabs leave as refugees for a variety of reasons among them, including: avoidance of crossfire, anticipation of war, expulsion, and the Jews massacre against number of Arab villages.
June 1948 : Violent confrontation between the Israel Defense Forces under the command of David Ben-Gurion, and the paramilitary Jewish group Irgun known as The Altalena Affair results in the dismantlement of the Irgun, Lehi, and all Israeli paramilitary organizations operating outside the IDF.
April 1949 : Israel concludes Armistice Agreements with neighbouring countries. The territory of the British Mandate of Palestine is divided between the State of Israel, the Kingdom of the Jordan (changed from Transjordan) and Egypt.