The fifth* of the British prime ministers
, from 1754 to 1756, then again from 1757 to 1762. He was a Whig
Born Thomas Pelham on 21st July 1693, he was educated at Westminster School and Claire Hall, Cambridge. He added the surname Holles to his own in 1711 (Thomas Pelham-Holles), and from that year also was known by the title Lord Pelham of Laughton. This was because he had succeeded to the estates, though not the title, of his uncle John Holles, Duke of Newcastle. (I'm sorry, but he's going to get even more confusing soon!) From 1714 he was Earl of Claire, and in 1715 he was created first Duke of Newcastle upon Tyne. (I presume that the old title had gone extinct with his uncle and this was therefore a re-creation.)
This is one of two completely separate, unrelated places in England, both called Newcastle, and he probably got fed up with people asking him "which one?" when he said he was Duke of Newcastle, because in 1756 he was also created first Duke of Newcastle-under-Lyme, presumably so that he could shout "both of them!". Course, by this time he was prime minister so he could get away with it.
In 1717 he married Lady Henrietta Godolphin, and they had no children, which must have been a sad disappointment to see the twin dukedom die with him.
He was appointed secretary of state by Sir Robert Walpole in 1724, joining his brother the secretary of war. He held this post for thirty years.
His first ministry began on 16th March 1754, ten days after the death of his brother, now prime minister Henry Pelham. It lasted until 26th October 1756. His successor was the Duke of Devonshire, who lasted until 1757. Devonshire's replacement the Earl of Waldegrave was unable to form a ministry, and on 2nd July 1757 Newcastle resumed office. He continued until 25th May 1762 (reappointed after the death of the king in 1760), when he was displaced by the Earl of Bute.
The real power in his ministry was however William Pitt the Elder, who was in charge of prosecuting the Seven Years War with France.
Newcastle died in London on 17th November 1768 and is buried near Lewes in Sussex, the same church as his brother. His wife died in 1776.
* fifth counting the Earl of Bath, who was appointed in 1746 but unable to form a ministry. Because numerous prime ministers served multiple disconnected terms, it is natural to number by the people, not the terms of office.
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