 The role of the Kingdom of Northumbria in the formation of the new style appears to have been pivotal.The northernmost Anglo-Saxon kingdom continued to expand into areas with Celtic populations, but often leaving those populations largely intact in areas such as Dál Riata, Elmet and the Kingdom of Strathclyde.The Irish monastery at Iona was established by Saint Columba (Colum Cille) in 563, when Iona was part of a Dál Riata that included territory in both Ireland and modern Scotland.