"The first President of Israel, Professor Chaim Weizmann - scientist and statesman - was among the leaders who were instrumental in the establishment of the State of Israel.
Born in 1874 in a small town in Russia, Chaim Weizmann received a combined Jewish and secular education. He pursued scientific studies in Germany and Switzerland and became involved in Zionist activities. In 1904 he immigrated to Great Britain and began his scientific career as a research chemist at Manchester University. During World War I he was acclaimed for his discovery of a method to produce synthetic acetone and came into contact with the "movers and shakers" of British society, among them Lord Balfour and Winston Churchill."
...
"Meeting with President Truman in March 1948, Weizmann impressed upon the President the importance of establishing a Jewish state. This was undoubtedly one of the factors for the speedy recognition of the State of Israel by the United States."

http://www.mfa.gov.il/mfa/go.asp?MFAH00gi0

"The Balfour Declaration
November 2, 1917

During the First World War, British policy became gradually committed to the idea of establishing a Jewish home in Palestine (Eretz Yisrael). After discussions in the British Cabinet, and consultation with Zionist leaders, the decision was made known in the form of a letter by Arthur James Lord Balfour to Lord Rothschild. The letter represents the first political recognition of Zionist aims by a Great Power.
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ARTICLE 22 OF THE COVENANT OF THE LEAGUE OF NATIONS, JUNE 28, 1919
THE FAISAL-WEIZMANN AGREEMENT, 1919
His Royal Highness the Amir Faisal, representing and acting on behalf of the Arab Kingdom of Hejaz, and Dr. Chaim Weizmann, representing and acting on behalf of the Zionist Organization, mindful of the racial kinship and ancient bonds existing between the Arabs and the Jewish people, and realizing that the surest means of working out the consummation of their national aspirations, is through the closest possible collaboration in the development of the Arab State and Palestine, and being desirous further of confirming the good understanding which exists between them, have agreed upon the following Articles:

Article I
The Arab State and Palestine in all their relations and undertakings shall be controlled by the most cordial goodwill and understanding and to this end Arab and Jewish duly accredited agents shall be established and maintained in their respective territories.

Article II
Immediately following the completion of the deliberations of the Peace Conference, the definite boundaries between the Arab State and Palestine shall be determined by a Commission to be agreed upon by the parties hereto.

Article III
In the establishment of the Constitution and Administration of Palestine all such measures shall be adopted as will afford the fullest guarantees for carrying into effect the British Government's Declaration of the 2nd of November, 1917.

Article IV
All necessary measures shall be taken to encourage and stimulate immigration of Jews in Palestine on a large scale, and as quickly as possible to settle Jewish immigrants upon the land through closer settlement and intensive cultivation of the soil. In taking such measures the Arab peasant and tenant farmers shall be protected in their rights, and shall be assisted in forwarding their economic development.

Article V
No regulation nor law shall be made prohibiting or interfering in any way with the free exercise of religion; and further the free exercise and enjoyment of religious profession and worship without discrimination or preference shall for ever be allowed. No religious test shall ever be required for the exercise of civil or political rights.

Article VI
The Mohammedan Holy Places shall be under Mohammedan control.

Article VII
The Zionist Organization proposes to send to Palestine a Commission of experts to make a survey of the economic possibilities of the country, and to report upon the best means for its development. The Zionist Organization will place the aforementioned Commission at the disposal of the Arab State for the purpose of a survey of the economic possibilities of the Arab State and to report upon the best means for its development. The Zionist Organization will use its best efforts to assist the Arab State in providing the means for developing the natural resources and economic possibilities thereof.

Article VIII
The parties hereto agree to act in complete accord and harmony in all matters embraced here before the Peace Congress.

Article IX
Any matters of dispute which may arise between the contracting parties shall be referred to the British Government for arbitration.

Given under our hand at London, England, 3rd day of January, 1919"
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