George Bryan "Beau" Brummell (7 June 1778 – 30 March 1840) was an important figure in Regency England, and for many years he was the arbiter of British men's fashion. At one time, he was a close friend of the Prince Regent, the future King George IV, but after the two quarrelled and Brummell got into debt, he had to take refuge in France. Eventually, he died from complications of neurosyphilis in Caen.

Brummell was remembered afterwards as the preeminent example of the dandy, and a whole literature was founded upon his manner and witty sayings, which have persisted until today. His name is still associated with style and good looks and has been given to a variety of modern products to suggest their high quality.

Brummell was born in Downing Street, London, the younger son of William Brummell (d. 1795), Private Secretary to the Prime Minister, Lord North, and Mary (née Richardson, daughter of the Keeper of the Lottery Office). North rated William Brummell highly, procuring for him appointments including those he held at the time of his death, namely Receiver of the Duties on Uninhabited Houses in London and Middlesex, Comptroller of the Hawkers' and Pedlars' Office, and Agent and Paymaster to the out-pensioners of Chelsea Hospital; these gave William about £2,500 per annum. On his retirement from politics, William had bought Donnington Grove in Berkshire and served as High Sheriff of Berkshire in 1788. William was the son of another William Brummell (d. 1770), who had been valet to a Lincolnshire politician, Charles Monson, and, reckoned "an excellent servant", met with some success despite his modest origins through patronage and good fortune; he went into business as a confectioner in Bury Street, "in an area notorious for [...] high-class brothels", letting some rooms in the family's house for boarding. The statesman Charles Jenkinson, 1st Earl of Liverpool, stayed there for a time and got the younger William a clerical position at the Treasury, which led to his successful career.

The family had achieved middle class status, but William Brummell was ambitious for his son George to become a gentleman, and he was raised with that understanding. It was suggested (possibly by the Brummells) that William Brummell was an illegitimate descendant of Frederick, Prince of Wales.

Brummell was educated at Eton College and made his precocious mark on fashion when he not only modernised the white stock, or cravat, that was the mark of the "Eton boy", but added a gold buckle to it.

He progressed to Oxford University, where, by his own example, he made cotton stockings and dingy cravats fall out of favour. While an undergraduate at Oriel College in 1793, he competed for the Chancellor's Prize for Latin Verse, coming second to Edward Copleston, who later became provost of his college. He left the university after only a year at age 16.

In June 1794, Brummell joined the 10th Light Dragoons, later the Tenth Royal Hussars as a cornet, the lowest rank of commissioned officer, and soon after had his nose broken by a kick from a horse. His father died in 1795, by which time Brummell had been promoted to lieutenant. His father had left him an inheritance of some £30,000. Ordinarily a considerable sum, it was inadequate for the expenses of an aspiring officer in the personal regiment of the Prince of Wales. The officers, many of whom were heirs to noble titles and lands, "wore their estates upon their backs – some of them before they had inherited the paternal acres." Officers in any military regiment were required to provide their own mounts and uniforms and to pay mess bills, but the 10th in particular had elaborate and nearly endless variations of uniform. Their mess expenses were unusually high because the regiment frequently enjoyed banquets and entertainment.

For such a junior officer, Brummell took the regiment by storm, fascinating the Prince: