Born on 13 September 1734 Thomas Thynne succeeded his father as 3rd Viscount Weymouth in January 1751 and was Lord Lieutenant of Ireland for a short time during 1765, although he never visited that country. Having, however, become prominent in English politics he was appointed Secretary of State for the Northern Department in January 1768; he acted with great promptitude during the unrest caused by John Wilkes and the Middlesex election of 1768. He was then attacked and libelled by Wiikes, who was consequently expelled from the House of Commons. Before the close of 1768 he was transferred from the northern to the southern department, but he resigned in December 1770 in the midst of the dispute with Spain over the possession of the Falkland Islands. In November Weymouth returned to his former office of secretary for the southern department, undertaking in addition the duties attached to the northern department for a few months in 1770, but he resigned both positions in the autumn of this year. In 1789 he was created Marquess of Bath, and he died in November 1796. Weymouth was a man of considerable ability, especially as a speaker, but according to more, modern standards, his habits were very coarse, resembling those of his friend and frequent companion, Charles James Fox. Horace Walpole refers frequently to his idleness and his drunkenness, and in early life at least "his great fortune he had damaged: by such profuse play, that his house was often full of bailiffs." He married Elizabeth (d. 1825), daughter of William Bentinck, 2nd Duke of Portland, by whom he had three sons and ten daughters.
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|width="30%" align="center"|Preceded by:
New Creation
|width="40%" align="center"|Marquess of Bath
|width="30%" align="center" rowspan="2"|Followed by:
Thomas Thynne
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|width="30%" align="center"|Preceded by:
Thomas Thynne
|width="40%" align="center"|Viscount Weymouth
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Text originally from 1911 Encyclopedia Britannica.