The Kingdom of Aksum, covering much of modern-day Eritrea and northern Ethiopia, was established during the first or second century AD. It adopted Christianity around the middle of the fourth century. In medieval times much of Eritrea fell under the Medri Bahri kingdom, with a smaller region being part of Hamasien. The creation of modern-day Eritrea is a result of the incorporation of independent, distinct kingdoms (for example, Medri Bahri and the Sultanate of Aussa) eventually resulting in the formation of Italian Eritrea. After the defeat of the Italian colonial army in 1942, Eritrea was administered by the British Military Administration until 1952. Following the UN General Assembly decision in 1952, Eritrea would govern itself with a local Eritrean parliament, but for foreign affairs and defense, it would enter into a federal status with Ethiopia for ten years. However, in 1962, the government of Ethiopia annulled the Eritrean parliament and formally annexed Eritrea. The Eritrean secessionist movement organised the Eritrean Liberation Front in 1961 and fought the Eritrean War of Independence until Eritrea gained ''de facto'' independence in 1991. Eritrea gained ''de jure'' independence in 1993 after an independence referendum.