With a population of around 80 million, Egypt is the most populous country in the Arab world, and the second most populous in Africa behind Nigeria. Its recorded history began in around 3100 B.C. when King Menes united the region, beginning a series of dynasties. The last dynasty fell to the Persians in 341 B.C., who in turn were replaced by the Greeks, Romans, and Byzantines. The Ottoman Turks controlled Egypt from 1517 until 1882 when Britain seized control of Egypt. In deference to growing nationalism, the United Kingdom declared Egyptian independence in 1922, but British influence continued to dominate Egypt's political life. In 1952 Egypt acquired full sovereignty with the overthrow of the British-backed monarchy, and it became a republic in 1953. Egypt has played a central role in Middle East politics in modern times. Its three wars with Israel in 1948, 1967 and 1973, followed by peace with its adversary in 1979, have transitioned Egypt from being a warring nation to becoming a key representative in the peace process. However, peace with Israel led to Egypt being expelled from the Arab League until 1989, and in 1981 President Sadat was assassinated by Islamic extremists. Since then, President Mubarak has taken a more moderate line, but Islamic groups have continued their campaigns sporadically, forging for deadly attacks that have often targeted tourists and resort areas. Egypt’s economy is the second largest in the Arab world -- following only Saudi Arabia. The country is a significant producer of oil and is a rapidly growing gas producer. Its economy is highly dependent on tourism revenues, oil and gas exports, remittances from Egyptian workers abroad, and revenue from the Suez Canal tolls.