The legacy of the Kingdom of Ireland remains a bone of contention in Irish-British relations to this day because of the constant ethnic conflict between the native Irish inhabitants and primarily the new Anglo-Irish settlers across the island. Their background espoused English culture (law, language, dress, religion, economic relations and definitions of land ownership) in Ireland as it later did across much of what was to become the British Empire. However Gaelic culture and Irish language, was maintained to a significant extent by the majority of the original native population. Sometimes this was presented as "barbaric", "savage" which later was perceived by the native population as a mark of undesirability in respect of maintaining and learning the language. While the Lordship of Ireland had existed since the 12th century and nominally owed allegiance to the English monarchy, many kingdoms of Gaelic Ireland continued to exist; this came to an end with the Kingdom of Ireland, where the whole island was brought under the centralised control of an Anglocentric system based in Dublin. This phase of Irish history marked the beginning of an officially organised policy of settler colonialism, orchestrated from London and the incorporation of Ireland into the British Empire (indeed Ireland is sometimes called "England's first colony"). The theme is prominently addressed in Irish postcolonial literature.