The land was spit because the British were leaving and the Jews and Arabs could barely stop killing each other for years before 1948. It was fought by the international community that the only way to try and stop a full on massacre or war was to spit the land. Two thirds went to the Arabs, which is now know as Jordan. One third to the Jews which Is Israel, west bank and Gaza. The Arab countries surrounding attacking in after declared a state meant the west bank and Gaza areas have changed control between different states a few times. Hence why it has been difficult for those civilians living there to find peace.
These are just a few examples of Arabs attacks on Jewish people on the land before 1948 when Israel declared themselves a state and why the international community came up with the plan because the British forces were leaving:
Safed looting 1834,
Hebron massacre 1834,
Attack on Safed 1838,
Jaffa deportations 1917,
Attack on Tel Hai 1920,
Jaffa riots 1921,
the riots 1929,
the riots in 1936
But other than that, life was not awsome before jews had independence!