Susan married the Duke of Manchester in
Edinburgh on 7 October 1793. They had eight children: • Lady Jane Montagu (1794–1815), who died unmarried. •
George Montagu, 6th Duke of Manchester (1799–1855). • Lord William Francis Montagu (1800–1842), who married Emily, third daughter of
James Du Pre, and had children. • Lady Georgiana Frederica Montagu (1803–1892), who married Evan Baillie of Dochfour and had children. • Lady Elizabeth Montagu, who married Thomas Steele and had children, including
Thomas Montagu Steele. • Lady Susan Montagu (c. 1801–1870), who married
George Hay, 8th Marquess of Tweeddale, and had children. • Lady Caroline Catherine Montagu (c.1804–1892), who married
John Hales Calcraft, MP and had children. • Lady Emily Montagu (1806–1827), who died unmarried. The duke was notoriously unfaithful, but it was the duchess who became the subject of a scandal when she left him for a footman. They separated and she was given a settlement. An exile from polite society, the duchess died at Bedfont Lodge in Middlesex, in August 1828, at the age of 54. She was buried at
Kimbolton. ==References==