Sir Leonard Holliday (also spelled Hollyday and Halliday; c. 1550 – 9 January 1612) was a founder of the East India Company, and a Lord Mayor of London.

He was born, perhaps circa 1550, in Rodborough in Gloucestershire, the son of clothmaker William Halliday and his wife Sarah Brydges.

[1] At some point, perhaps in the late 1560s, he was sent to London, where he served an apprenticeship in the Worshipful Company of Merchant Taylors, which controlled the men's garment industry in the city.

While membership was open to the public (known as 'the generality'), executive control was restricted to the merchant élite, and Leonard was not only one of the original 'committees' (i.e. directors) but also joint treasurer from 1600 until 1602.

As Lord Mayor, Sir Leonard was responsible for maintaining public order during the trial and execution of the conspirators in January 1606.

[7] The lasting legacy of Sir Leonard's lord mayoralty was the redevelopment of the Moorfields, a swamp just north of the city wall.