Portugal emerged as a unified kingdom in the 12th century It became a major maritime power in the 15th century, opening new seaways to the east and the west, and built a vast colonial empire. The decline came with the destruction of Lisbon by an earthquake and tidal wave in 1755, and Brazil's independence in the 19th century. In 1910 a revolution deposed the monarchy. Political chaos and economic problems led to a long period of dictatorship, which ended with the left-wing military coup in 1974. A year later democracy was firmly installed, and Portugal's colonies in Africa recovered independence. Economically, Portugal has been one of the least advanced countries in Europe. During the economic boom in western Europe in the 1950-70s, many Portuguese emigrated to the richer countries to find work. In 1986 the country joined the European Community (now EU), and during the 1990s it achieved economic growth above the EU average. Portugal is a Catholic country. For a long time, the Catholic Church enjoyed the privilege of concordat between the Vatican and the Portuguese state. The tiny Presbyterian, Methodist, and Anglican churches grew out of 19th century missionary work, and form together the Council of Christian Churches. The largest independent churches are the controversial Universal Church of the Kingdom of God, which has come from Brazil, and the Mana Church from South Africa. The Jehovah's Witnesses form also a sizeable and growing group. The Assemblies of God (Pentecostal) and Evangelical churches like the Baptists, Seventh-day Adventists, and Brethren are also present. The Evangelical Alliance of Portugal is affiliated with the WEA.