She divided us in life, she’s dividing us in death. Baroness Thatcher was so controversial that a single letter in a single word in the subtitle of a book that someone else has written about her and is being published after her funeral can get people’s backs up. Charles Moore’s biography is, according to its cover, ‘authorized’. Iain Dale isn’t happy (and I’m sure he’s not alone). ‘I am appalled,’ he writes on his blog, ‘that they have used the American spelling … It’s certainly not what she would have wanted and it grates. Penguin ought to remember its British roots.’

Good news, Iain – it turns out ‘-ize’ isn’t American after all. It’s as British as Yorkshire pudding and socks with sandals. Or rather it’s English, dating as it does from the time before Britain even existed. The first recorded example of ‘organize’, for instance, according to the Oxford English Dictionary, was in 1425. ‘Realize’ appeared in 1611. The earliest ‘-ise’ the OED can do you is 1755. Even the chap whose birthday we’ve been celebrating this week tended to favour ‘z’ over ‘s’: there’s ‘sympathized’ in The Comedy of Errors, ‘canonized’ in Henry VI Part II, while Othello talks of an ‘unauthorized kiss’. ‘Authorized’ was also used by Coleridge, John Ruskin, Samuel Johnson and Walter Scott.

It wasn’t until the early 1800s that ‘-ise’ really headed up the charts. By then Noah Webster was trying to standardise language over the pond, writing his massively influential American Dictionary of the English Language (1828). He plumped for ‘-ize’. Therefore some Brits, in the years since, have come to mistake it for a Yank import. When the z-version had a resurgence over here in the years before World War II, lots of our chaps argued against it, straining themselves purple to insist that ‘-ise’ was the correct – that is to say British – spelling. But to this day the Oxford University Press retain ‘-ize’ as their house style.

And if OUP aren’t convincing enough, I refer you to no less an authority than Susie Dent, who as Queen of Countdown’s Dictionary Corner is a figure nearly as intimidating as Thatcher herself. ‘I almost always choose “-ize”,’ she says. ‘It makes sense in etymological terms, because it corresponds to the Greek verb endings “-izo” and “-izein”. There’s no wrong and right: as long as you know when not to use “z” with the verbs that absolutely aren’t spelled that way – such as “excise”, for instance – then you can take your pick. But it’s definitely the case that “-ize” isn’t an Americanism: it started life in England well before any settlers crossed the Atlantic.’

So there we are. We can all relax. Anyway, even if “-ize” was an Americanism, it wouldn’t have bothered the Blessed Margaret: Special Relationship and all that. Just as long as there weren’t any French phrases in the book.

Join us for ‘An Evening with Charles Mooreon 7 May, where Andrew Neil will discuss the life of Baroness Thatcher with her official biographer, sharing his unique insights into this towering political figure of our times. Click here to book tickets.

Tags: Language, Margaret Thatcher, Non-fiction, Shakespeare