Complex sentence: His paternal grandfather was the 9th Baron Ferrers of Chartley, who was created Viscount Hereford in 1550, and by his mother he was a nephew of Henry Bourchier, a former Earl of Essex.
Split into simpler sentences: His paternal grandfather was the 9th Baron Ferrers of Chartley, who was created Viscount Hereford in 1550. Through his mother, Walter was a nephew of Henry Bourchier, a former Earl of Essex.