Complex sentence: The Ó Cadhla (Kealy) clan were the rulers of Connemara up until the 13th century when they were displaced from this position by the O Flahertys who fled into Iar Connacht from Maigh Seola during the English invasion of Connacht in the early 1200s.
Split into simpler sentences: The Ó Cadhla (Kealy) clan were the rulers of Connemara up until the 13th century, when they were displaced by the O Flahertys. The latter had fled into Iar Connacht from Maigh Seola during the English invasion of Connacht in the early 1200s.