Complex sentence: The rector of St Oswald's for several decades was Rev. Robert More, who died in 1642, who was father-in-law of the English explorer Capt. Christopher Levett.
Split into simpler sentences: The rector of St Oswald's for several decades was Rev. Robert More, who died in 1642. He was the father-in-law of the English explorer, Capt. Christopher Levett.