26 April 1964; Tanganyika became independent 9 December 1961 (from UK-administered UN trusteeship); Zanzibar became independent 19 December 1963 (from UK); Tanganyika united with Zanzibar 26 April 1964 to form the United Republic of Tanganyika and Zanzibar; renamed United Republic of Tanzania 29 October 1964
28 November 1975 (independence proclaimed from Portugal); note - 20 May 2002 is the official date of international recognition of Timor-Leste's independence from Indonesia
England has existed as a unified entity since the 10th century; the union between England and Wales, begun in 1284 with the Statute of Rhuddlan, was not formalized until 1536 with an Act of Union; in another Act of Union in 1707, England and Scotland agreed to permanently join as Great Britain; the legislative union of Great Britain and Ireland was implemented in 1801, with the adoption of the name the United Kingdom of Great Britain and Ireland; the Anglo-Irish treaty of 1921 formalized a partition of Ireland; six northern Irish counties remained part of the United Kingdom as Northern Ireland and the current name of the country, the United Kingdom of Great Britain and Northern Ireland, was adopted in 1927
22 May 1990 (Republic of Yemen was established with the merger of the Yemen Arab Republic [Yemen (Sanaa) or North Yemen] and the Marxist-dominated People's Democratic Republic of Yemen [Yemen (Aden) or South Yemen]); note - previously NorthYemen became independent in November 1918 (from the Ottoman Empire) and became a republic with the overthrow of the theocratic Imamate in 1962; SouthYemen became independent on 30 November 1967 (from the UK)