The severing of Captain Jenkins's ear, in 1731, attached little attention at the time, but it became something of a cause célèbre in 1738 after Jenkins was ordered to testify before Parliament – presumably to repeat his story before a committee of the House of Commons. Parliament subsequently voted to ask the King (George II) to seek redress from Spain. A squadron of warships was sent to the West Indies in July 1739, and war was declared in October. By 1742 the war had become subsumed in the War of the Austrian Succession.
It's often said that Jenkins actually presented his severed ear to the Commons committee, but there is no actual evidence to support this claim.
The war was given its unusual name in 1858 – well over 100 years after the cessation of hostilities – by the Scottish historian Thomas Carlyle. I was gratified to discover that Carlyle actually had called it "the War of Jenkins's Ear", and that the final "s" had been dropped at some later date (by person or persons unknown). I read in Ernest Gowers's Plain Words that the only time you drop the "s" after an apostrophe that indicates a possessive is when the word that comes before the apostrophe is a plural ending in "s". "Jenkins" is not a plural, so it's "Jenkins's Ear" and not "Jenkins' Ear".
Other examples: "the boys' bicycles", "the Joneses' car" (dropping the "s", because these are both plurals ending in "s"); but "the women's jobs", "Mr. Jones's car", and "the bus's wheels" (not dropping the "s", because in the first example the word before the apostrophe doesn't end in "s", and in the last two it isn't a plural).
Unfortunately I seem to have mislaid my copy of Gowers, so I can't quote chapter and verse.
© Haydn Thompson 2017