Did Victorian writers in Britain use ‘-ise’ or ‘-ize’?

A friendly reader recently commented to me that in using the suffix ‘ize’ (e.g. organize) I was adopting American English spellings rather than British English. I’ve been checking the copy edits of the third Arrowood book, and the issue has come up again: what form would a Victorian writer from London use? I found this very useful post from Hannah Kate that goes some way to answering the question. It seems that Victorians used both suffixes, although ‘ise’ gradually became more popular.

Here’s a quote from that article:

While the American -ize/-ise distinction was tidied up and codified by Webster and his successors, Britain continued on with its somewhat haphazard habits. In the nineteenth century, the worm began to turn and -ise began to reassert itself. Again, this coincided with both a general drive to ‘tidy up’ the somewhat higgledy-piggledy English language and the introduction of new technologies. Just as the invention of the printing press played a role in the standardization of spelling and grammar, the industrialization of the printing process and the rise of commercial publishers furthered the move towards a consistent(ish) set of spelling rules. This was the age of Henry Alford insisting that it is wrong to ever split an infinitive, and of Robert Lowth stating that a preposition is a bad thing to end a sentence on.

What’s strange, though, is that while late eighteenth- and early nineteenth-century grammar rules almost invariably looked to classical languages for their authority – e.g. infinitives should not be split in English because they can’t be split in Latin – the non-Latinate -ise suffix grew in popularity. To me, it feels like split infinitives and -ize endings have a lot in common, and yet it was during the reign of Victorian grammarians that -ise returned to dominance. (From Hannah Kate, In Defence of -ize)