The story of the Balfour Declaration is well-known: On 2 November 1917, in the midst of World War I, Britain's Foreign Secretary, Lord Balfour, signed a letter promising Jews a "national home" in Palestine.

That short letter is now celebrated by Jews and mourned by Arabs. Little-known, but recorded in scholarly books (notably by Benny Morris, in "Righteous Victims: A History of the Zionist-Arab Conflict, 1881-1999") are the intense intrigues of the time, with France five months ahead of Britain in issuing a pro-Zionist statement and Britain worried that the enemy, Germany, was going to do the same.

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The war in Europe was bogged down in bloody and mud-filled trenches. But in the Middle East, the centuries-old Ottoman Empire, fighting alongside Germany, was coming apart. That November, British and other forces were driving Turkish soldiers and their German advisers out of Palestine.

The Middle East was crucial to Britain – both the oil in the emerging new states and also the Suez Canal, giving access to India and other colonies. Together with France, Britain was already deciding which new Middle East countries to create and control, leaving only Turkey as the rump of the empire.

At the same time, influential Jews in Britain were pressing their government to support Zionism, 20 years after Theodor Herzl gave voice to the goal of a state for Jews, to end the centuries of persecution.

Open gallery view Lord Balfour Credit: Agence RoI

They were aided by fortuitous circumstances: Dr Chaim Weizmann was not only an eminent Russian-born scientist at Manchester University who gave inestimable help to Britain’s war effort by developing chemicals for munitions, but he was also president of the British Zionist Federation.

A man of striking ability and charismatic personality, he was a friend and trusted confidant of the elite in Britain, ranging from C.P. Scott, editor of The Manchester Guardian (now The Guardian) who backed Zionist aspirations, to David Lloyd George, who became prime minister in December 1916, and Lord Balfour, his foreign secretary.

Across the Channel, the French foreign ministry thought Jews were influential in Russia, in the collapsing Tsarist regime, and also wanted Jewish support for a post-war French presence in Palestine.

On 4 June 1917 the French foreign ministry issued the Cambon Letter, a statement that it approved a text presented to it by Zionists that "circumstances permitting, and the independence of the Holy Places being safeguarded... it would be a deed of justice and of reparation to assist, by the protection of the Allied Powers, in the renaissance of the Jewish nationality in the land from which the people of Israel were exiled so many centuries ago." It went on: "The French government cannot but feel sympathy for your cause, the triumph of which is bound up that of the Allies."

The French perhaps meant the statement to be mere words without a commitment to action. But the fact of it opened the way to Britain issuing its own statement of support for Zionism, especially as Lloyd George, with British imperialist interests at heart and determined to protect the Suez Canal area, wanted to keep out the French.

Palestine under British control or protection was desirable. He and other colleagues were also devout Christians who had fundamental beliefs derived from the Old Testament about the justice of the Jewish cause. Lord Balfour later explained that he and Lloyd George had been influenced "by the desire to give Jews their rightful place in the world; a great nation without a home is not right".

Open gallery view People gather in the streets of Tel Aviv after radio broadcasts announce UN plan for partition of Palestine and the new Jewish state, November 30, 1947. Credit: AP

Not everyone agreed. Important contrary voices were heard: Lord Curzon told a Cabinet meeting that Palestine was mostly "barren and desolate... a less propitious seat for the future Jewish race could not be imagined". He did not seem to have said this out of concern for Jews for, as he also said, Zionism was "sentimental idealism, which would never be realised" and anyway "how could the Jews ever overcome the far more and stronger Arabs".

The pro-Zionists, in the Cabinet and the foreign office, insisted on following on France’s example. They were joined by another highly influential leader, Jan Christiaan Smuts from South Africa. A general in the Boer forces fighting the British army in the Anglo-Boer War at the turn of the century, he now had the unusual distinction of being a colonial in the inner recesses of the British government, as a member of the Imperial War Cabinet.

Lloyd George and Balfour and others such as Winston Churchill, the Colonial Secretary, also believed that a declaration in favour of a Jewish state would bring Jewish influence and power worldwide to bear on the side of the Allies. They were concerned about keeping Russia on their side and thought Jewish influence in that country could help do this – which, given the violent anti-Semitism of the Tsarist regime, reveals their remarkable ignorance, or at best, naivete.

Also, in an astonishing irony in history, Britain's leaders were worried that Germany was about to issue a statement in support of a Jewish state in Palestine. This, they feared, could push German-born Jews in the United States, who had no allegiance to the Allied Powers, to influence the U.S. not to enter the war (this factor disappeared on 7 April 1917 when the US entered the war on the side of the Allies). They were, too, thoroughly alarmed at any prospect that Germany might gain a foothold in the Middle East area so vital to British strategic interests.

Out of this medley of factors came the Balfour Declaration, actually a brief letter. It was first submitted to President Woodrow Wilson of the United States, who did not object to it. Lord Balfour then sent it to Lord Rothschild, the head of Britain’s Zionist Federation:

"His Majesty’s Government view with favour the establishment in Palestine of a national home for the Jewish people and will use their best endeavours to facilitate the achievement of this object, it being clearly understood that nothing shall be done which may prejudice the civil and religious rights of existing non-Jewish communities in Palestine or the rights and political status enjoyed by Jews in any other country."

Immediately, this became the charter of the Zionist movement, to transform the words of promise into reality. Success took less than 31 years: the state of Israel was created on 14 May 1948.

Open gallery view Jordan's King Abdullah meeting with Prime Minister Benjamin Netanyahu at the royal palace in Amman, Jordan on July 27, 2010. Credit: Avi Ohayon

Later, in 1922, the League of Nations, the world body set up to ensure peace forever – that was the intention – sanctified the Middle East carve-up.

Britain was given a mandate for Palestine, with the aim of fulfilling the Balfour Declaration. But Winston Churchill was also negotiating with Arab leaders about their demands for land, and so he had the details redrafted: Britain was no longer obliged to foster a Jewish state east of the Jordan River. At the same time, Britain also surrendered land in the north of Palestine, handing it to France, which had been given a mandate for Lebanon.

The upshot was that in 1921 the land east of the Jordan River – forming 75 percent of Palestine – was hived off as Transjordan. It was meant to be temporary, to provide a haven for Abdullah, one of the Arabian princes at war with each other.

Weizmann protested, writing to Churchill to note that "the fields of Gilead, Moab and Edom, with the rivers Arnon and Jabbok are historically and geographically and economically linked to Palestine, and it is upon these fields, now that the rich plains of the north have been taken from Palestine and given to France, that the success of the Jewish National Home must largely rest..."

Yet other Zionist leaders did not campaign strongly against it. They believed it was only temporary. However, Transjordan went its own way, and under British tutelage.

In 1946, Britain asked the new United Nations Organisation to end its mandate and the territory became today’s Hashemite Kingdom of Jordan. The remaining 25 percent of Palestine remained under British mandate rule, until 1948, when it became today's Israel, the West Bank and the Gaza Strip.