The 9th Regiment of Foot was a infantry

Infantry

Infantrymen are soldiers who are specifically trained for the role of fighting on foot to engage the enemy face to face and have historically borne the brunt of the casualties of combat in wars. As the oldest branch of combat arms, they are the backbone of armies...

 line regiment of the British Army

British Army

The British Army is the land warfare branch of Her Majesty's Armed Forces in the United Kingdom. It came into being with the unification of the Kingdom of England and Scotland into the Kingdom of Great Britain in 1707. The new British Army incorporated Regiments that had already existed in England...

 from 1751 to 1881. It became the Norfolk Regiment following the Army reforms of 1881.
The title of 9th Foot was awarded in 1751, but the origins of the regiment are with Henry Cornewall's Regiment of Foot raised by James II

James II of England

James II & VII was King of England and King of Ireland as James II and King of Scotland as James VII, from 6 February 1685. He was the last Catholic monarch to reign over the Kingdoms of England, Scotland, and Ireland...

 in 1685 in response to the Monmouth Rebellion

Monmouth Rebellion

The Monmouth Rebellion,The Revolt of the West or The West Country rebellion of 1685, was an attempt to overthrow James II, who had become King of England, King of Scots and King of Ireland at the death of his elder brother Charles II on 6 February 1685. James II was a Roman Catholic, and some...

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The regiment fought in the Williamite war in Ireland

Williamite war in Ireland

The Williamite War in Ireland—also called the Jacobite War in Ireland, the Williamite-Jacobite War in Ireland and in Irish as Cogadh an Dá Rí —was a conflict between Catholic King James II and Protestant King William of Orange over who would be King of England, Scotland and Ireland...

, seeing action at the Battle of the Boyne

Battle of the Boyne

The Battle of the Boyne was fought in 1690 between two rival claimants of the English, Scottish and Irish thronesthe Catholic King James and the Protestant King William across the River Boyne near Drogheda on the east coast of Ireland...

 and Battle of Aughrim

Battle of Aughrim

The Battle of Aughrim was the decisive battle of the Williamite War in Ireland. It was fought between the Jacobites and the forces of William III on 12 July 1691 , near the village of Aughrim in County Galway....

, as well as the siege of Limerick (1690)

Siege of Limerick (1690)

Limerick, a city in western Ireland, was besieged twice in the Williamite War in Ireland, 1689-1691. On the first of these occasions, in August to September 1690, its Jacobite defenders retreated to the city after their defeat at the Battle of the Boyne...

, and siege of Limerick (1691)

Siege of Limerick (1691)

Limerick in western Ireland was besieged twice during the Williamite War in Ireland . The city, held by Jacobite forces was able to beat off a Williamite assault in 1690. However, after a second siege in August-October 1691, it surrendered on terms....

 and siege of Athlone

Siege of Athlone

Athlone in central Ireland, was besieged twice during the Williamite War in Ireland . The town is situated on the River Shannon and commanded the bridge crossing the river into the Jacobite held province of Connaught...

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