Downing was the only son of
Sir George Downing, 2nd Baronet, and his wife, Lady Catharine Cecil, daughter of
James Cecil, 3rd Earl of Salisbury. His
grandfather, who was created a baronet in 1663, was the namesake of
Downing Street. Lady Catharine died in 1688, and, as her husband was apparently considered an unsuitable parent, the young George was brought up in the family of his maternal aunt, Lady Mary Cecil Forester, the wife of
Sir William Forester of Dothill Park, in
Wellington, Shropshire. In 1700, aged 15, "by procurement and persuasion of those in whose keeping he was", he married his 13-year-old cousin, Sir William's daughter, Mary, who ultimately died childless in 1734. Between his marriage and 1704 he travelled in Europe, mainly
Holland,
Germany,
Denmark and
Italy. While George was away, Mary went against George's explicit demand that she should not accept a place at court, when she became a Maid of Honour to
Queen Anne. On George's return, it was apparent that the marriage had broken down. The couple agreed a financial settlement only in 1715, whereupon Mary petitioned the House of Lords to have the marriage dissolved because of non-consummation. The petition was refused and they remained married. They jointly petitioned again in 1717, asking for a separation, which was granted. That made them legally independent, with no responsibility to one another. However, neither could remarry, and neither could have a legitimate heir. He was a
Member of Parliament for the
pocket borough of
Dunwich,
Suffolk in the
parliaments of 1710 and 1713. He lost the 1715 election but, with the aid of a 99-year lease from
George I for the borough, regained the seat in 1722. He held the seat from that time until his death. ==Death and estate==