The modern apostrophe s or s apostrophe for possession comes ultimately from the Old English (aka Anglo-Saxon) genitive case. Old English like modern German had different cases (inflections) to express grammatical relationships such as subject, direct object, indirect object, and possession. The most common possessive inflection was -es. When the e stopped being pronounced it gradually dropped out of the spelling but was replaced by the apostrophe to show that it "should" be there. Over time this was extended to include all possessives whether or not they had originally had an e. The idea that 's is short for his is a myth.

Bingley

Bingley