The Balfour Declaration of November 1917 is considered a major development in the transformation of the Middle East.
European Jews had been subjected to brutal attacks by the governments of the countries in which they resided. Always considered outsiders despite generations having lived in particular areas, and always the victim of violent attacks and discrimination, a movement was formed in the lat 19th Century known as Zionism. The leader of the Zionist movement was Theodor Herzl, a Jew living in the Austria-Hungarian empire. Herzl and his followers postulated that the key to the survival of the Jewish people in the face of endemic antisemitism in Europe was to return to the place where Judiasm began, Palestine.
World War I saw the colonial European powers Great Britain and France on one side of the conflict and the Turkish Ottoman Empire siding with Germany and Austria-Hungary on the other side. The Ottoman Empire controlled large swathes of Arabia, while the British and French sought to maintain their hold on colonies in the Middle East and North Africa. In the meantime, the U.S. Administration of President Wilson included prominent Jewish-Americans who advocated on behalf of the establishment of a Jewish homeland in Palestine.
In an attempt to weaken the Austria-Hungarian/German/Ottoman axis while currying favor with the U.S. Administration, the British government began to support the Zionist movement. The Balfour Declaration, named for the British Foreign Secretary of the time, formalized that government's support for the establishment of the Jewish homeland in Palestine, with the caveat that such a development could not adversely affect the "civil and religious rights of existing non-Jewish communities in Palestine..."[The Balfour Declaration]
The Balfour Declaration today stands as a major affront to the Arab peoples of the Middle East. The establishment of the State of Israel in 1948, following the death of six million European Jews in the Holocaust, represents, to the Arabs, a European intrusion into the Islamic Nation. To this day, Arabs view Israel as a European colony forced upon them for the sins of the Europeans. The Jews argue that they have a right to a homeland in Palestine by virtue of their history there and the prevalence of their most important religious sites in what is today Israel and the West Bank (or, Judea and Samaria).