[nq:1]I see we have some Old English cognoscenti in this forum so I wondered if someone could confirm or otherwise, ... [/nq] The simple answer is that seventeenth-century grammarians got it into their heads that the possessive '-s' (no longer '-es' by this time) was actually a contraction of 'his' (the man his hat - a form of locution that became popular at the beginning of the seventeenth century). They therefore took to indicating this supposed 'contraction' by using the apostrophe.
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