Somerled (died 1164), known in Middle Irish as Somairle, Somhairle, and Somhairlidh, and in Old Norse as Sumarliði [ˈsumɑrˌliðe], was a mid-12th-century Norse-Gaelic lord who, through marital alliance and military conquest, rose in prominence to create the Kingdom of Argyll and the Isles. Little is certain of Somerled's origins, although he may have been born in the north of Ireland and appears to have belonged to a Norse–Gaelic family of some prominence. His father, GilleBride, of royal Irish ancestry, appears to have conducted a marriage alliance with Máel Coluim mac Alaxandair, son of Alexander I of Scotland, and claimant to the Scottish throne. During a period of alliance with David I of Scotland, Somerled married Ragnhild, daughter of Óláfr Guðrøðarson, King of Man and the Isles in 1140. In 1153, Olaf of Man died and was succeeded by his son, Godred. But Godred Olafsson was a very unpopular ruler. Somerled was asked by Thorfinn Ottarson, a Manx chief, to allow Somerled's son, Dugall, to be appointed king of Man and the Isles. Somerled agreed and with 80 ships confronted Godred off the coast of Islay on January 5–6, 1156. After the sea battle, Somerled and Godred divided the Kingdom of Man and the Isles between them but Godred did not accept Dugall as King of Man. Accordingly, two years later, Somerled defeated and drove Godred from power. Dugall continued as King of Man and Somerled thus ruled the entire kingdom of Argyll, Man and the Isles until his death.
Somerled was slain in 1164 at the Battle of Renfrew, amidst an invasion of mainland Scotland, commanding forces drawn from all over his kingdom. The reasons for his attack are unknown. He may have wished to nullify Scottish encroachment, but the scale of his venture suggests that he nursed greater ambitions. On his death, Somerled's vast kingdom disintegrated, although his sons retained much of the southern Hebridean portion. Compared to his immediate descendants, who associated themselves with reformed religious orders, Somerled may have been something of a religious traditionalist. In the last year of his life, he attempted to persuade the head of the Columban monastic community, Flaithbertach Ua Brolcháin, Abbot of Derry, to relocate from Ireland to Iona, a sacred island within Somerled's sphere of influence. Unfortunately for Somerled, his demise denied him the ecclesiastical reunification he sought, and decades later his descendants oversaw the obliteration of the island's Columban monastery. Iona's oldest surviving building, St Oran's Chapel, dates to the mid-12th century, and may have been built by Somerled or his family.
