What started the craze for using "z" instead of "s" to pluralise words?

Like "boyz", for example?

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Goes way back, particularly in attempts, to write down accents, or slang.
Seen it at least as far back as the 20,,

Later, came the desire to "misbehave"
"Oh does it bother you i spell it wrong"
Ha ha ha ha

And of course the ancient one.
"Kaint rilly spel"