Bayning was the only son of the Honorary William Townshend, third son of Charles Townshend, 2nd Viscount Townshend. His mother was Henrietta Powlett, daughter of Lord William Powlett.
On his mother"s side he was a female-line great-great-grandson of Anne, Viscountess Bayning, daughter of Paul Bayning, 1st Viscount Bayning.
Bayning was educated at Eton and Clare College, Cambridge.
In 1756 he was elected to the House of Commons for Great Yarmouth, a seat he held until 1784, and served as a Lord of the Admiralty from 1765 to 1770, as a Lord of the Treasury from 1770 to 1777 and as Joint Vice-Treasurer for Ireland from 1777 to 1782. Between April and December 1783 he was Treasurer of the Navy in the Fox-North Coalition. In 1777 Bayning was admitted to the Privy Council.
The following year he was raised to the peerage as Baron Bayning, of Foxley in the County of Berkshire. in 1807 he served as High Sheriff of Great Yarmouth.
He lived at Honingham Hall in Norfolk. Lord Bayning married Annabella Smith-Powlett, daughter of Reverend Richard Smith and Annabella Powlett, in 1777.
Lady Bayning died in 1825.
11th Parliament of Great Britain. 12th Parliament of Great Britain. 13th Parliament of Great Britain.
14th Parliament of Great Britain.
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He returned as Member of Parliament for Great Yarmouth in 1790, and continued to represent this constituency until 1796.
