eli5: In english the s is sometimes contracted (she’s/she is or she has) but what does the s stand for when it’s possessive? Like the king’s crown? What word is that s?

Question

Truth be told, 90% of my english comes from Skyrim and Doctor Who, I remeber very few rules from my school days and it’s been bugging me for days and my research skills are bringing me no fruit. Help?

In: 14

Answer 1

In my 15 seconds of googling, apparently English used to put “es” at the end of words to show possession. The.example they gave mentioned “The Kinges garb…”

So I guess ‘s is just an abbreviation of “es”