Thatcher appointed Lord Carrington, an ennobled member of the party and former Secretary of State for Defence, to run the Foreign Office in 1979. Although considered a "wet", he avoided domestic affairs and got along well with Thatcher. One issue was what to do with Rhodesia, where the white-minority had determined to rule the prosperous, black-majority breakaway colony in the face of overwhelming international criticism. With the 1975 Portuguese collapse in the continent, South Africa (which had been Rhodesia's chief supporter) realised that their ally was a liability; black rule was inevitable, and the Thatcher government brokered a peaceful solution to end the Rhodesian Bush War in December 1979 via the Lancaster House Agreement. The conference at Lancaster was attended by Rhodesian prime minister Ian Smith, as well as by the key black leaders: Muzorewa, Mugabe, Nkomo and Tongogara. The end result was the new Zimbabwean nation under black rule in 1980.