George Onslow was born on 13th September 1731. His father, Arthur, was Speaker of the House of Commons from 1728 to 1761.

George followed his father into politics being the MP for Rye from 1754-61 and for Surrey from 1761-74.

He was created Baron Cranley in 1776 and succeeded to the Onslow Barony the same year. He was created the first Earl Onslow in 1801.

George Onslow died on 17th May 1814.