Mostly over the treatment of "uitlanders"--foreigners living in the Transvaal and working in the mines of the Rand.  The uitlanders were mostly British and American. They were denied most civil right for up to fourteen years (mostly to prevent them from voting and upsetting Boer control over Transvaal. British desire (esp. Cecil Rhodes) to gain political control over the mineral riches of the Transvaal British Diplomat Milner's continual provocation of Transvaal President Paul Kruger. Milner viewed the Boer Republics in Transvaal and Orange Free State as absurdities who needed to be under British control Wilhelm II of Germany's statements encouraged the Boers to war with Britain.  They expected German help. The Jameson Raid was a clumsy attempt to start a rebellion among the uitlanders in Transvaal by Cecil Rhodes