[2] Robert Mor Munro was a staunch supporter and faithful friend of Mary, Queen of Scots and he consequently was treated favourably by her son James VI.
George Buchanan states, that when the unfortunate princess went to Inverness in 1562 and found the gates of the castle shut against her; "as soon as they heard of their sovereign's danger, a great number of the most eminent Scots poured in around her, especially the Frasers and Munros, who were esteemed the most valiant of the clans inhabiting those countries in the north".
Andrew Munro, 5th of Milntown defended and held, for three years, Chanonry Castle, which he had received from the Regent Moray who died in 1569, against the Clan Mackenzie, at the expense of many lives on both sides.
:[11] The Munros defended and keipt the Castle for the space of thrie yeirs, with great slaughter on either syd, vntill it was delyvered to the Clanchenzie, by the Act of Pacification.
[13] As a reward for his faithful services to the Crown, Robert Mor Munro obtained from King James VI, a grant of all the customs due as royalties "furth of the town and Sheriffdom of Inverness", as registered under the Privy Seal, dated at Edinburgh on 5 January 1572.
[2] Robert Mor Munro was also one of the members of a Commission appointed to act as Sheriffs of Inverness, for serving Alexander Gordon, 12th Earl of Sutherland, on 30 May 1573.
[14] In 1585, Robert Mor Munro signed a bond of manrent with George Gordon, 1st Marquess of Huntly to assist each other as allies against any person except for the King or Queen.
Others included are Gordon of Huntly, Mackenzie of Kintail, Rose of Kilravock, Fraser of Lovat, Grant of Freuchie and Ross of Balnagowan.
[17] On 20 July 1588 Robert Mor Munro of Foulis was appointed by the King, collector, for Inverness-shire, which included Ross.
On the 27th of that month, Robert Mor Munro of Foulis along with Colin Cam Mackenzie of Kintail are appointed Commissioners for the shires of Inverness and Cromarty for the better administration of justice in these counties.