The First Anglo-Boer War (1880–1881), was a rebellion of Boers (farmers) against British rule in the Transvaal that re-established their independence. The conflict occurred against the backdrop of the Pretoria government becoming increasingly ineffective at dealing with growing claims on South African land from rival interests within the country. The Second War (1899–1902), by contrast, was a lengthy war—involving large numbers of troops from many British possessions, which ended with the conversion of the Boer republics into British colonies (with a promise of limited self-governance). These colonies later formed part of the Union of South Africa. The British fought directly against the Transvaal and the Orange Free State, defeating their forces first in open warfare and then in a long and bitter guerrilla campaign. British losses were high due to both disease and combat. This war saw so many nationalities fighting against each other, and was at the same time a civil war involving Afrikaner against Afrikaner, and South African English-speakers, as well as many black combatants, fighting and dying on both sides.