Complex sentence: One sept that did survive was the Clann Breasil, surnamed Ó Domhnalláin Donnellan, who, based at Ballydonnellan, Loughrea, became notable bards of Connacht and Munster.
Split into simpler sentences: One sept that did survive was the Clann Breasil. Based at Ballydonnellan, Loughrea, they became notable bards of Connacht and Munster.