Gaelic Ireland was a Gaelic political and social order that existed in Ireland from sometime in prehistoric era until the early 17th century. Before the Norman invasion of 1169, Gaelic Ireland comprised the whole island. Thereafter, it comprised that part of the country not under English or at least foreign dominion at a given time. For most of its history, Ireland was a 'patchwork' hierarchy of territories ruled by a hierarchy of kings or chiefs, who were elected by a system known as tanistry. Warfare between these territories was common. Occasionally, a powerful ruler was acknowledged as High King of Ireland. Society was separated into kin groups and, like the rest of Europe, was structured hierarchically according to class. Throughout this period, the economy was mainly pastoral and money generally not used. A Gaelic Irish style of dress, music, dance, sport, architecture, and art can be identified, with Irish art later merging with Anglo-Saxon styles from Great Britain developing Insular art.