It was supposed to have been a nice soft landing: a colonial assignment that married the twilight of a capable if unremarkable diplomatic career to the governorship of an obscure British outpost at the twilight of empire.

“A tranquil but absorbing posting” was the way the British Foreign Office described the job, Sir Rex Hunt later recalled.

And thus he was dispatched in 1980 to take charge of the Falkland Islands, a windblown archipelago in the South Atlantic, nearly 8,000 miles from England, where sheep outnumbered people by more than 300 to 1.

As Sir Rex, who died on Nov. 11 at 86, could scarcely have imagined, his colonial idyll would end abruptly in 1982, when he found himself, literally overnight, directing a tiny band of British military men against an amphibious Argentine invasion....