After the Great War, the British Government did keep one of her many wartime promises to her allies.
In a letter dated November 2nd, 1917, towards the end of the Great War, Foreign Secretary Arthur Balfour assured prominent banker Lord Rothschild that the British Government would do what it could to carve out a homeland for Jewish people in what was then part of the Ottoman Empire. The promise was kept, and this is how the Colonial Office List for 1946 summarised the formation of British Mandatory Palestine.