The sitter was the eldest son of Francis North, 3rd Baron and later 1st Earl of Guilford (1704-1790) and his first wife Lady Lucy Montagu (d. 1734; see lot 56), daughter of George, 1st Earl of Halifax. He attended Eton College (1742-8) and Trinity College, Oxford, after which he went on a Grand Tour with his step-brother William Legge, 2nd Earl of Dartmouth (1731-1801), the son of his father's second wife Elizabeth, Viscountess Lewisham (d. 1745; see lot 59). North began his political career with the general election of 1754, when he entered Parliament representing the single-member borough of Banbury. He held the post unchallenged until he succeeded his father as 2nd Earl of Guilford on 4 August 1790. On 20 May 1756, North married Anne (c. 1740-1797), daughter and heir of George Speke of White Lackington, Somerset. They had seven children (for a portrait of the couple's second son Francis North, 4th Earl of Guilford, see lot 64). North's fledgling political career was aided by a number of useful family connections as well as his much-praised abilities as an orator, and by 1759 he had been appointed a Lord of the Treasury. North moved rapidly upward through the hierarchy; in 1767 he was made chancellor of the exchequer at the urging of the King, and by 1768 he had become the unofficial leader of the house. In 1770, he became first Lord of the Treasury and subsequently Prime Minister, a post he held for 12 years. In 1772, the King, a close personal friend of North's, awarded him the Garter - an honour given to only one other commoner that century, Sir Robert Walpole.
Though North was responsible for important steps in reducing the tremendous national debt, as well as resolving potential conflicts in India, Ireland and Canada, his time in office has historically been remembered for the American War of Independence, which began brewing in 1773 with the Boston Tea Party in defiance of English taxation. North attempted to maintain control of the rebel colonies with measures such as the Boston Port Act and Massachusetts Government Act, but by 1775 war appeared inevitable. By 1782 North was pleading with a stubborn George III for permission to negotiate peace, and in the spring of that same year he offered his resignation.
The present portrait is after the original by Nathaniel Dance in the National Portrait Gallery, London. Numerous versions exist, both attributed to Dance in full and some believed to be studio products. There are engravings by T. Burke (1775), Warren, W.T. Mote, R.H. Cromek, and E. Bocquet.