It has long been a land divided, a small patch of Earth where Israelis and Palestinians share little except, as a famous Irish poet said of his own land, "great hatred and little room."

In the beginning, at least at the beginning of the 20th century, it was a backwater, a forgotten corner of empire. The empire was Turkish, the Ottoman Empire. The land was Palestine and there were almost no Jews.

But 90 years ago, on Nov. 2, 1917, something happened that would create a conflict that would run like a tributary of blood through the century.

David Lloyd George, the Welsh nationalist was British prime minister from 1916 to 1922 and was a key figure at the Paris Peace Conference in 1919. (Hulton Archive/Getty Images)

In London, a letter was written. It was short. Its author was the British foreign secretary, Lord Arthur Balfour. Its recipient was Lord Rothschild, a prominent British Jew. The content was explosive.

The British government, it said, "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."

At that time, Jews were no more than eight per cent of the population of Palestine. Zionists were overjoyed. The small movement launched in its modern form by Theodor Herzl had only taken root 20 years earlier.

Now a great imperial power was backing its goal.

Why then?

Why did Britain make such a promise? The answer, perhaps not surprisingly, was war and empire.

The First World War was grinding its way through millions of men. For the British prime minister of the day, David Lloyd George, the declaration was a desperate throw of the dice to try to keep Russia engaged on the side of Britain.and France.

The Russian Revolution had just taken place and the Bolsheviks in power were calling for the country to pull out of the fighting. Even more important, Lloyd George was desperate for the United States to plunge into the conflict with enthusiasm, men, money and machines.

"The British and French were bleeding to death on the Western Front," observes British historian David Cesarani, who specializes in modern Jewish history.

"Lloyd George thought that maybe, if he could swing Jewish opinion in Russia behind the Allies, that might keep Russia in the war. And if he could win over Jewish opinion in America, maybe that would push America into the war on the side of the Allies.

"And what would be the key to winning Jewish opinion? The promise to set up a Jewish national home in Palestine. That was the crucial trigger for the Balfour declaration."

The road from 1919

The Balfour declaration was, as Lloyd George wrote later, a military decision that wildly overestimated the influence of the Jews in both Russia and the U.S. when it came to the war.

But empire still played a role in it going forward. The Ottomans were fighting on the side of the Germans in the First World War. Defeated, these Turkish territories in the Middle East would be ripe for plucking. And the British wanted to box out the French.

Thus the play for Palestine as a homeland for Jews, but to be administered by the British.

At the Paris Peace Conference in 1919, Britain was duly given a mandate to rule Palestine. The World Zionist Organization came to the conference and presented a map of what it saw as the future Jewish homeland. It looked remarkably like a map of modern Israel that included Gaza and the West Bank.

With the end of the First World War, however, British leaders began to regret their commitment to a Jewish homeland. There were fewer than 60,000 Jews in Palestine, facing more than 500,000 Arabs.

"The British government found that its army was policing a potential Jewish national home with a tiny number of Jews faced by a very large number of angry Arabs," Cesarani says. "This was a nightmare."

Balfour's legacy

Lord Arthur Balfour, a Scottish parliamentarian was Britain's prime minister from 1902-1905 and came out of retirement to be Lloyd George's foreign secretary in 1916. (Getty Images)

The Arabs in Palestine were not even mentioned by name in the Balfour declaration. They were simply referred to as non-Jewish peoples.

After the war, the British colonial secretary saw the commitment to a Jewish homeland as an unnecessary burden on the empire. He tried to appease the Arabs by hiving off a territory from Palestine known today as Jordan and giving it to the Hashemite dynasty. The colonial secretary was Winston Churchill.

But appeasement didn't work. There were periodic explosions of violence: In 1920, 1921 and again in 1929. Then came an Arab uprising, which began in 1935.

Jews, galvanized by the Balfour declaration and, more importantly, by the lash of Hitler from 1933 on, continued to pour in. By the mid 1930s there were almost 400,000 Jews in Palestine, 30 per cent of the population. The Arabs then feared that they would be swamped within a few decades.

At that point, the British did what governments do. They set up another commission, the third since Balfour, under Lord Peel.

In 1937, it concluded there were "irreconcilable national aspirations" and, for the first time, recommended the partition of Palestine into Jewish and Arab-controlled entities.

In the brief span of 20 years, groping for policies to win a war and consolidate an empire, Britain had outlined the future Middle East — a Jewish homeland in a territory divided.

According to Cesarani, the Peel partition idea "was a very far-sighted proposal."

After a while, he says, "the British government ditched it because it was afraid of a very powerful Arab backlash. The emerging Arab states would not tolerate even a mini-Jewish state in Palestine or the Palestinian territories.

"Of course, in the end partition was what the UN decided and what the Jews agreed to."

In the wake of the Second World War, Britain began to shed its empire. It abandoned its mandate in Palestine in 1948. The Jews immediately proclaimed the state of Israel and fought for and won its survival.

Now another imperial power, based in Washington, oversees the region and its troubles.

It periodically sends out emissaries, including its secretary of state, with gifts and threats. It talks of a yet another conference to find diplomatic solutions. The Israeli and Palestinian leaders meet but resolve nothing.

Yet Balfour, Cesarani says, has left a powerful history.

"It gave the Jews a place in the world. And you could say that, as well as the troublesome legacy of the Balfour declaration, that is a pretty miraculous legacy."

The Jewish homeland is now a state. Partition is now a fact on the ground even if there is not yet a second state for the Palestinians. The legacy of Balfour is both miraculous and bloody and bitter.

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