In an interview available on youtube, Lord Jacob Rothschild explains the significance of the Balfour declaration, which was addressed to his grandfather Lord Walter Rothschild and signed by the British Foreign Minister, Lord Arthur Balfour on behalf of His Majesty's Government in 1917. The Balfour declaration was the Empire's imprimatur for the creation of 'a national home for the Jewish people' in Palestine. It expressed 'sympathy with Jewish Zionist aspirations'.
The Balfour declaration was a major fillip for the World Zionist Organisation that had been created twenty years earlier by Theodore Herzl to pursue the goal of Jewish nationalism. But as Lord Rothschild noted in his interview, the declaration had a couple of problems, namely it stipulated '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'.
While these stipulations certainly sound reasonable, they were at odds with the goal of the Zionists and have been completely disregarded ever since.