A half-length portrait to right in a feigned oval. He wears a brown silk coat and brown full-bottomed wig. Pepys's fame derives both from the private diary he kept from 1660 to 1669, which gives a unique insight into both his times and his character, and from his importance as a Naval administrator over a much longer period from 1660, initially under the patronage of his cousin, Edward Montagu, first Earl of Sandwich. When Sandwich was killed at the Battle of Solebay in 1672, James, Duke of York became his patron, notwithstanding the Duke's exclusion from office as Lord High Admiral in the following year. Pepys also won the confidence of James's elder brother, Charles II.

He was initially Clerk of the Acts (Secretary of the Navy Board) and, from 1686 to 1688, Secretary of the Admiralty, where he created a modern state department out of an archaic office. He left the Admiralty in February 1689 after his patron - now James II - was driven into exile by the 'Glorious Revolution' of 1688 that put William and Mary (James's daughter) on the throne. The portrait was thus painted by Kneller during a turbulent year for Pepys, and is inscribed and dated on the back 'Mr Pepes G.Kneller fecit 1689'. It is one of three portaits, painted for him at that time, the others being of his former secretary and faithful friend William Hewer (BHC2765), with whom he lived in retirement at Clapham until his death, and John Jackson, his nephew. The pictures remained in Pepys's family until Pepys and Hewer purchased for the Museum by Sir James Caird in 1931; the location of Jackson is unknown (it was sold to an R. H. Muir). This one was first engraved in a small format by Robert White in 1690 (see PAD2688). Another version was engraved by T. Bragg in 1827 as frontispiece for volume 1 of the octavo five-volume (second) edition of Pepys's diary of 1828, and subsequent re-issues (see PAI9572).