Since the declaration of Israel's establishment in 1948, conflict has existed between Israel and the surrounding Arab countries, rooted in conflict over territory also claimed by Palestinian Arabs. Zionists viewed the region of Palestine as the Jewish ancestral homeland, while Arabs saw it as Arab Palestinian land and an essential part of the Arab world. By 1920, sectarian conflict had begun with the dissolution of the Ottoman Empire and the partition of Ottoman Syria by the 1916 Sykes–Picot treaty between Britain and France that became the basis for the Mandate for Palestine and the 1917 Balfour Declaration that expressed British support for "the establishment in Palestine of a national home for the Jewish people."