Welsh national identity emerged among the Celtic Britons after the Roman withdrawal from Britain in the 5^th century, and Wales is regarded as one of the modern Celtic nations. Edward I of England conquered Wales in 1282, though there was a brief independent Welsh period in the early 15^th century. The whole of Wales was annexed by England and incorporated within the English legal system under the Laws in Wales Acts 1535-1542. Distinctive Welsh politics developed in the 19^th century. Welsh Liberalism, exemplified in the early 20^th century by Lloyd George, was displaced by the growth of socialism and the Labour Party. Welsh national feeling grew over the century; Plaid Cymru was formed in 1925 and the Welsh Language Society in 1962. Established under the Government of Wales Act 1998, the National Assembly for Wales holds responsibility for a range of devolved policy matters.