[2] Maclean was born in Cairo, Egypt to Major Charles Wilberforce Maclean OBE DSO (1875–1953), a member of the Scottish minor nobility serving in Egypt with the Queen's Own Cameron Highlanders,[3] and Frances Elaine Gladys Royle (1882–1954),[4] the only daughter of George Royle, a Royal Navy officer and Fannie Jane Longueville Snow, who wed on 12 July 1905 at St George's Church, Hanover Square, London.

Although he was stationed in the capital, Maclean travelled extensively, primarily by train, into remote regions of the USSR which were off limits to foreigners, and was shadowed by the NKVD as he did so.

In North Africa in 1942, Maclean distinguished himself in the early actions of the newly-formed Special Air Service (SAS), where, with Ralph A. Bagnold, he developed ways of driving vehicles over the Libyan sand "seas".

Don't be taken in by his rather pompous manner or his slow way of speaking – he is OK."[7] Later that year Maclean transferred to the Middle East as part of the Persia and Iraq Command.

He was "allotted a platoon of Seaforth Highlanders and instructed to kidnap" General Fazlollah Zahedi, the commander of the Persian forces in the Isfahan area.

Maclean's relationship with Tito's Partisans was not always easy, partly because they were Communist, while he came from an upper class Scottish background, and had witnessed Stalinism in action (see above).

"[15] On 9 July 1949, Maclean laid the foundation stone of the Overton & District Memorial Hall in his Lancaster constituency, where he was president of the committee that had raised the money to purchase the land and build it.

He also contributed to other books, for example writing the foreword to a 1984 biography of Joseph Wolff, the so-called "Eccentric Missionary" in whose footsteps he had travelled to Bukhara almost half a century before.

[22] In the late 1960s, Maclean bought Palazzo Boschi,[23] a villa on the Adriatic island of Korčula (present-day Croatia),[24] where he spent a good part of each year.

[26] In 1991, during the Croatian War of Independence, Maclean and his wife delivered medical supplies to the island of Korčula, with a substantial contribution from the people of Rothesay and Bute.

She was a daughter of Simon Fraser, 14th Lord Lovat, and widow of naval officer, Lieutenant Alan Phipps, who was killed ashore at Leros in 1943.

[28] Sir Fitzroy and Lady Maclean had two sons,[29][30] and he was also stepfather to his wife's children from her first marriage: Major-General Jeremy Phipps and Suki Marlowe.

[35] He was succeeded in the baronetcy by his elder son, the Much Honoured Sir Charles Maclean, Baron of Strachur, and 16th Hereditar Keeper and Captain of Dunconnel in the Isles of The Sea.