Complex sentence: Sir Valentine Browne was the first of the family to settle in Ireland, with his son, also Valentine Browne, in 1588--the year of the Armada--he made an agreement with MacCarty Mor for a lease on the lands of Coshmang and Ross.
Split into simpler sentences: Sir Valentine Browne was the first member of the family to settle in Ireland, with his son, also Valentine Browne, in 1588, the year of the Armada. He made an agreement with MacCarty Mor for a lease on the lands of Coshmang and Ross.