<P> The nature of British identity has changed over time . The island that contains England, Scotland, and Wales has been known as Britain from the time of the Roman Pliny the Elder (c . AD 23--79). English as the national language had its beginnings with the Anglo - Saxon invasion of c. 450 A.D. Prior to this the inhabitants spoke mainly various Celtic languages . The various constituent parts of the present United Kingdom joined at different times . Wales was annexed by the Kingdom of England under the Acts of Union of 1536 and 1542 . However, it was not until 1707 with a treaty between England and Scotland, that the Kingdom of Great Britain came into existence . This merged in January 1801 with the Kingdom of Ireland to form the United Kingdom of Great Britain and Ireland . Until fairly recent times Celtic languages continued to be spoken in Scotland, Wales, Cornwall, and Ireland, and still survive, especially in parts of Wales </P> <P> Subsequently, the impact of Irish nationalism led to the partition of the island of Ireland in 1921, which means that literature of the Republic of Ireland is not British, although literature from Northern Ireland is both Irish and British . </P> <P> Works written in the English language by Welsh writers, especially if their subject matter relates to Wales, has been recognised as a distinctive entity since the twentieth - century . The need for a separate identity for this kind of writing arose because of the parallel development of modern Welsh - language literature . </P> <P> Because Britain was a colonial power the use of English spread through the world, and from the nineteenth - century in the United States, and later in other former colonies, major writers in English, including Nobel laureates, began to appear beyond the boundaries of Britain and Ireland . </P>

What is the start of american and british literature