A funny thing," grins George lain Murray as 80 kilted Highlanders perform their twice-annual trooping of the color on the grounds of Scotland's Blair Castle, "I'm totally unmilitary." A funny thing indeed, for as the 10th Duke of Atholl, His Grace is commander in chief of the last private army in Europe.

The duke, mind you, has no phantom jets or ICBMs gleaming at the ready on his 135,000-acre estate near Perth. His troops, mostly ducal employees and all volunteers, are the ceremonial remnants of a once mighty force that held sway in Scotland until the Battle of Culloden in 1746. A century later Queen Victoria repaid her hosts after a stay at Blair by granting them rights to retain their private army—a move that also sealed Clan Murray's reconciliation with the British crown. The last time Atholl's army fired a shot in anger was in 1808, when it manned an Irish garrison during the Napoleonic wars. Its only recent conquests have been tourists.

By the time the present duke, who is 47, succeeded to the title in 1957, his forces had dwindled to eight hangers-on. "A bit thin even for ceremonies," recalls the duke, who hastily beefed up the ranks. "But since I have no idea what to do, I leave it to them."

The hereditary colonel (that's his rank) is in residence only every other weekend. Atholl cramps his 6'3½" frame into a sleeper for the 470-mile journey by rail from London, where he keeps a townhouse. He stays in Blair's south end, which was staff quarters, and for $1.85 apiece allows rubber-neckers to tramp through the main part of the 200-odd-room castle.

The 10th duke was born in London, the third cousin three times removed of the ninth duke, but nonetheless heir to the 275-year-old title, which passes down only through the male line. Atholl was 13 when his father, a merchant banker, was killed during World War II. At Eton and Oxford he got average grades; his mother remembers that he played bridge and liked to study the racing form. At 22, relying on his mother's contacts—she is one of Britain's powerful banking and publishing Cowdrays—he landed a job at a family fiefdom, Westminster Press, which operates 12 dailies and 65 weeklies. Four years ago Atholl succeeded his mother as chairman of the board. Also, he reports, "I make a nuisance of myself" twitting Scottish nationalists in the House of Lords.

As to who will be the 11th duke and colonel, bachelor Atholl isn't sure. Since both of his brothers died in infancy, first in line these days is a 79-year-old third cousin living in Tanzania. But the most likely successor is Bruce Murray, 18-year-old son of an even more distant relative. Young Murray lives in South Africa, and he and the duke have never met. "I just might go out," Atholl says, "and have a look at him." Whatever happens, sighs His Grace, Britain's capital transfer tax and death duties will cause "hideous problems" for his heirs.

As for marriage, Atholl is "not entirely ruling it out. I would very much like to have a direct heir. But I feel rather schizophrenic about it. You see, I don't get along terribly well with children." He isn't at ease in his regalia as Highlanders' colonel either. "Very uncomfortable," Atholl grimaces while disentangling himself from tartan and silver-buckled belt. But for one or two days a year, he concedes, "it's fun."

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