Óláfr Guðrøðarson, also known as Olaf the Black, was a thirteenth-century King of the Isles, and a member of the Crovan dynasty. He was a son of Guðrøðr Óláfsson, King of the Isles and Fionnghuala Nic Lochlainn. Óláfr was a younger son of his father; Óláfr's elder brother, Rǫgnvaldr, probably had a different mother. According to the Chronicle of Mann, Guðrøðr appointed Óláfr as heir since he had been born "in lawful wedlock". Whether or not this is the case, after Guðrøðr's death in 1187 the Islesmen instead appointed Rǫgnvaldr as king, as he was a capable adult and Óláfr was a mere child. Rǫgnvaldr ruled the island-kingdom for almost forty years, during which time the half-brothers vied for the kingship.

The Kingdom of the Isles was a Norse-Gaelic kingdom comprising the Isle of Man, the Hebrides and the islands of the Clyde from the 9th to the 13th centuries AD. The islands were known to the Norsemen as the Suðreyjar, or "Southern Isles" as distinct from the Norðreyjar or Northern Isles of Orkney and Shetland. In Scottish Gaelic, the kingdom is known as Rìoghachd nan Eilean. The territory is sometimes called the Kingdom of Mann and the Isles, although only some of the later rulers claimed that title. The historical record is incomplete, and the kingdom was not a continuous entity throughout the entire period. At times the rulers were independent of external control, although for much of the period they had overlords in Norway, Ireland, England, Scotland or Orkney. At times there also appear to have been competing claims for all or parts of the territory. The islands have a total land area of over 8,300 square kilometres (3,205 sq mi) and extend for more than 500 kilometres (310 mi) from north to south.