Sir John Munro, 4th Baronet of Foulis (died c. September 1697), 22nd Baron and 25th chief of the Clan Munro, was such a strenuous supporter of Presbyterianism, that, being of a large frame, he was known as "the Presbyterian mortar-piece."
In the Stuart persecutions, previous to his succession to the title, he had for his adherence to the covenant, been both fined and imprisoned by the tyrannical government that then ruled Scotland. As John Munro had been fined and imprisoned as a Covenanter, at the Glorious Revolution he naturally took the side of William of Orange.
In 1661, by a deed dated 23 January, John entered into a bond of friendship and manrent with Kenneth Mor Mackenzie, 3rd Earl of Seaforth, chief of MacKenzies. They became bound to each other for themselves and for their friends to live as good neighbours and to assist and defend each other.
John is also mentioned in a minute of agreement between George Sinclair, Earl of Caithness and George Gordon, Lord Strathnaver who later became the 14th Earl of Sutherland, dated 7 December 1668, as one of the Earl of Cathness's and Earl of Argyll's 'Deputies' in the Sheriffship and Justiciary. The other Deputes are Lord Strathnaver himself, Ross of Balnagowan and Sir George Munro of Glenurquhie.
John died in 1697. John married Agnes, daughter of Sir Kenneth Mackenzie, 3rd Earl of Seaforth chief of the Clan Mackenzie. They had six children.