Complex sentence: He was born in Lethenborough, Buckinghamshire, the 5th son of Sir Richard Ingoldsby and his wife Elizabeth Cromwell, the daughter of Sir Oliver Cromwell (died 1655), who was the uncle and godfather of Oliver Cromwell.
Split into simpler sentences: He was born in Lethenborough, Buckinghamshire, the 5th son of Sir Richard Ingoldsby and his wife Elizabeth Cromwell. She was the daughter of Sir Oliver Cromwell (died 1655), who was the uncle and godfather of Oliver Cromwell.