I have never realised that that apostrophe rule existed alemci
If you want to add to your apostrophe knowledge, you know all that stuff about there being two sorts of apostrophe, the ones use for omission (don't, isn't) and the one used for possession (Dave's dog's basket)?
There's really only one sort, omission.
Shakespeare et al only use it for omission and for vowels that aren't sounded. So what's now rendered (Tempest, I.1) "Take in the topsail. Tend to the master's whistle. Blow, till thou burst thy wind,if room enough!" is "Take in the toppe-sale: Tend to th' Masters whistle: Blow till thou burst thy winde, if roome enough." in the first folio (and subsequent editions of the 17th century).
Printers had started to use the apostrophe to mark vowels that weren't pronounced any more (for example, it's quite common to see modern "loved" spelt "lov'd"). Old English had a genitive case ("godes lof" = "God's love"), which had disappeared over time (Comedy of Errors, I.2, "For Gods sake send some other messenger"). Sometimes this was printed as "God's" because of a vestigial awareness of the "missing" e. Eventually, in the 18th century it was standardised for possession, including for cases where there actually wasn't a missing e ("the gate's hinges"). The pronouns were already irregular in OE and hadn't changed other than the spelling being regularised ("Cnut cyning gret his arcebiscopas" = "Cnut King greets his archbishops") so they didn't acquire apostrophes (hence all the confusion over its).
The plural possessive case ("my three dogs' bowls") didn't get standardised until the 19th century. OE had the ending -as for this case, but I think the convention of putting an apostrophe after the s was pretty much invented from whole cloth. Someone who actually understands this stuff might comment.