Lord Tichfield, the eldest son of the 2nd Duke of Portland, studied at Oxford, and entered parliament in 1761 before going to the Lords when he succeeded his father as Duke of Portland the next year. Associated with the aristocratic Whig party of Charles Watson-Wentworth, 2nd Marquess of Rockingham, Portland served as Lord Chamberlain of the Household in Rockingham's first Government (1765-1766), and then as Lord-Lieutenant of Ireland in Rockingham's second ministry (April-August 1782), but resigned from Lord Shelburne's ministry along with other supporters of Charles James Fox following Rockingham's death.
In April, 1783, Portland was brought forward as titular head of a coalition government whose real leaders were Charles James Fox and Lord North. He served as First Lord of the Treasury in this ministry until its fall in December of the same year.
Along with many other conservative Whigs (such as Edmund Burke), Portland was deeply uncomfortable with the French Revolution, and ultimately broke with Fox over this issue, joining Pitt's government as Home Secretary in 1794. He continued to serve in the cabinet until Pitt's death in 1806 - from 1801 to 1805 as Lord President of the Council, and then as a Minister without Portfolio.
When Pitt's supporters returned to power after the collapse of the Ministry of all the Talents in March, 1807, Portland was, once again, an acceptable figurehead for a fractious group of ministers who included George Canning, Lord Castlereagh, Lord Hawkesbury, and Spencer Perceval.
Portland's second government saw England's complete isolation on the continent, but also the beginning of recovery, with the start of the Peninsular War. In late 1809, with Portland's health poor and the ministry rocked by the scandalous duel between Canning and Castlereagh, Portland resigned, dying shortly thereafter.
The Duke of Portland's First Ministry, April - December 1783
The Duke of Portland's Second Ministry, March 1807 - October 1809
Changes
{| border="2" align="center"
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|width="30%" align="center"|Preceded by:
William Bentick
|width="40%" align="center"|Duke of Portland
|width="30%" align="center"|Followed by:
William Cavendish-Scott-Bentick
|}