Complex sentence: Her parents were both from wealthy families with strong ties to the British peerage and intellectual life, and she married Edward Montagu, a wealthy man with extensive holdings, to become one of the wealthiest women of her era.
Split into simpler sentences: Her parents were both from wealthy families with strong ties to the British peerage and intellectual life. She married Edward Montagu, a wealthy man with extensive holdings, to become one of the wealthiest women of her era.