Complex sentence: His family's political dynasty ensured that Medows was a well connected parliamentarian; he had been on good terms with Horace Walpole, the son of Prime Minister Sir Robert Walpole.
Split into simpler sentences: His family's political dynasty ensured that Medows was a well connected parliamentarian. He had been on good terms with Horace Walpole, the son of Prime Minister Sir Robert Walpole.