Together with his twin brother, Oliver, he was initially educated at Huntingdon Grammar School,[1] from where they were summoned to meet Samuel Pepys (a family friend): The two twins were sent for from schoole, at Mr. Taylor's, to come to see me, and I took them into the garden, and there, in one of the summer-houses, did examine them, and do find them so well advanced in their learning, that I was amazed at it: they repeating a whole ode without book out of Horace, and did give me a very good account of any thing almost, and did make me very readily very good Latin, and did give me good account of their Greek grammar, beyond all possible expectation; and so grave and manly as I never saw, I confess, nor could have believed; so that they will be fit to go to Cambridge in two years at most.

[2]The boys transferred to Westminster School and thence to Trinity College, Cambridge, where John entered as a fellow-commoner on 12 April 1672, proceeded MA.

He died unmarried, at his house in Bedford Row, Holborn, London, on 23 February 1728, aged 73, and was interred at Barnwell, Northamptonshire, the burying-place of his family.

[5][6] Trinity College is said to have declined in numbers or reputation during Montagu's mastership, on account of the relaxation of discipline which his easy temper encouraged.

This sum had been claimed by his successor, Dr. Richard Bentley, and the above compromise was not effected until 1702, when the thanks of the society were given to Montagu, and his name inscribed in the register of benefactors by the master.