Newcastle vigorously sustained the Whigs at Queen Anne's death and had much influence in making the Londoners accept King George I, even organising so-called 'Newcastle mobs' to fight with rival Jacobites in the street.

His services were too great to be neglected by the new Hanoverian king, and in 1714, he was created Earl of Clare, and in 1715 Duke of Newcastle-upon-Tyne, two titles previously held by his late uncle John Holles.
He also became Lord-Lieutenant of the Counties of Middlesex and Nottingham and a Knight of the Garter.
In his new position, he was in charge of suppressing Jacobitism in the counties under his control.
In Middlesex, he arrested and questioned 800 people and drew up a Voluntary Defence Association to defend the county.
In 1715, he became involved in a riot that ended with two men being killed, and Newcastle fleeing along rooftops.
The succession of George I was secured in late 1715 by the defeat of a Jacobite army at the Battle of Preston and the subsequent flight of the Old Pretender.

The victory of the Hanoverians over the Jacobites marked the beginning of the Whig Ascendancy which lasted for much of the 18th century.
Because the Tory opposition had been tainted, in the eyes of George I, by their support of the Jacobite pretenders, he did not trust them and drew all of his ministers and officials from the Whigs.
Following their victory, the Whigs split with one group forming the government for George I, and the other dissident Whigs became the effective opposition in Parliament.
After a period of political manoeuvring, he was for a while associated with a Whig faction led by James Stanhope, but from 1720, Newcastle began to identify strongly with the government Whigs, who had quickly come to be dominated by Sir Robert Walpole.

Walpole gladly welcomed the young Newcastle into his coterie because Walpole believed that he could easily control Newcastle and because it would strengthen Walpole's hand against the rival Whig factions.
Newcastle joined with Walpole because Newcastle, correctly, believed that Walpole was going to dominate British politics for a generation.
In 1721, Walpole began to serve as Britain's first prime minister and would that position for the next 21 years.
He was related to Walpole's leading ally, Charles Townshend, strengthening his bond with the leader of the new administration.

On 2 April 1717, he increased his Whig connections by marrying Lady Henrietta Godolphin, the granddaughter of the Duke of Marlborough, a national hero following his victories in the recent European war who was considered a Whig icon.
Newcastle vigorously sustained the Whigs at Queen Anne's death and had much influence in making the Londoners accept King George I, even organising so-called 'Newcastle mobs' to fight with rival Jacobites in the street.
His services were too great to be neglected by the new Hanoverian king, and in 1714, he was created Earl of Clare, and in 1715 Duke of Newcastle-upon-Tyne, two titles previously held by his late uncle John Holles. He also became Lord-Lieutenant of the Counties of Middlesex and Nottingham and a Knight of the Garter. In his new position, he was in charge of suppressing Jacobitism in the counties under his control. In Middlesex, he arrested and questioned 800 people and drew up a Voluntary Defence Association to defend the county. In 1715, he became involved in a riot that ended with two men being killed, and Newcastle fleeing along rooftops. The succession of George I was secured in late 1715 by the defeat of a Jacobite army at the Battle of Preston and the subsequent flight of the Old Pretender.
The victory of the Hanoverians over the Jacobites marked the beginning of the Whig Ascendancy which lasted for much of the 18th century. Because the Tory opposition had been tainted, in the eyes of George I, by their support of the Jacobite pretenders, he did not trust them and drew all of his ministers and officials from the Whigs. Following their victory, the Whigs split with one group forming the government for George I, and the other dissident Whigs became the effective opposition in Parliament. After a period of political manoeuvring, he was for a while associated with a Whig faction led by James Stanhope, but from 1720, Newcastle began to identify strongly with the government Whigs, who had quickly come to be dominated by Sir Robert Walpole.
Walpole gladly welcomed the young Newcastle into his coterie because Walpole believed that he could easily control Newcastle and because it would strengthen Walpole's hand against the rival Whig factions. Newcastle joined with Walpole because Newcastle, correctly, believed that Walpole was going to dominate British politics for a generation. In 1721, Walpole began to serve as Britain's first prime minister and would that position for the next 21 years. He was related to Walpole's leading ally, Charles Townshend, strengthening his bond with the leader of the new administration.
On 2 April 1717, he increased his Whig connections by marrying Lady Henrietta Godolphin, the granddaughter of the Duke of Marlborough, a national hero following his victories in the recent European war who was considered a Whig icon.
Thomas Pelham-Holles, 1st Duke of Newcastle