Baron Howard of Marnhull

Marquessate of Northampton
Arms of Compton: Sable, a lion passant guardant or between three esquire's helmets argent
Creation date	1547 (first creation; forfeit 1554-59) 1812 (second creation)
Monarch	Edward VI (first creation) Elizabeth I (first creation, restoration) George III (second creation)
Peerage	Peerage of the United Kingdom (second creation)
First holder	William Parr, 1st Marquess of Northampton (first creation)
Present holder	Spencer Compton, 7th Marquess of Northampton (second creation)
Heir apparent	Daniel Compton, Earl Compton
Remainder to	Heirs male of the body, lawfully begotten
Subsidiary titles	Earl of Northampton (fourth creation) Earl Compton Baron Wilmington
Extinction date	1571 (first creation)
Seat(s)	Castle Ashby House Compton Wynyates
Armorial motto	Je ne cherche qu'un (I seek but one)

Marquess of Northampton is a title that has been created twice, firstly in the Peerage of England (1547), then secondly in the Peerage of the United Kingdom (1812). The current holder of this title is Spencer Compton, 7th Marquess of Northampton.

The title of Marquess of Northampton was created for the first time in the Peerage of England in 1547 in favour of William Parr, brother of Catherine Parr, the sixth and last wife of King Henry VIII. The title was forfeited in 1554 after the accession of Queen Mary but restored in 1559 by Queen Elizabeth I. On Parr's death in 1571, the title became extinct.

However, the title is chiefly associated with the Compton family. This family descends from Sir Henry Compton, who in 1572 was summoned to the House of Lords as Baron Compton, of Compton in the County of Warwick. This title was in the Peerage of England. Lord Compton was later one of the peers at the trial of Mary, Queen of Scots. He was succeeded by his son, the second Baron. He served as Lord President of the Marches and of the Dominion of Wales and was also Lord Lieutenant of Warwickshire. In 1618 he was created Earl of Northampton in the Peerage of England.

His son, the second Earl, was a supporter of King James I and served as Master of the Robes to Charles, Prince of Wales (later King Charles I). He fought in the Civil War and was killed at the Battle of Hopton Heath in 1643. He was succeeded by his son, the third Earl. He also fought as a Royalist in the Civil War and notably commanded the cavalry at the First Battle of Newbury in 1643. Lord Northampton was also Lord Lieutenant of Warwickshire and Constable of the Tower of London. His eldest son, the fourth Earl, also served as Constable of the Tower of London and as Lord Lieutenant of Warwickshire.