The school was founded in 1597 by Richard Platt, owner of a City of London brewery and Master of the Worshipful Company of Brewers in 1576 and 1581.

In 1596, Queen Elizabeth I granted him letters patent to build "the Free Grammar School and Almshouses" at Aldenham; the foundation stone was laid in 1597.

[citation needed] A Stanley Spencer painting of The Crucifixion was commissioned by the Master of the Brewers Company, for the Aldenham School Chapel in 1958.

The school was visited during the year by The Princess Royal, who came to open the new artificial turf pitch that had been built as a result of money raised by the appeal.

Consequently Aldenham School arguably had the earliest organised football club in the history of the game (a distinction often awarded to Sheffield which began 29 years later in 1854).

The founder, Richard Platt, arranged that when there was a vacancy, St John's College, Cambridge, was to nominate three Masters of Arts, from whom the Brewers' Company would appoint one.