Yeah is indeed from yea, from Old English gea. All three were originally pronounced identically, but yea underwent a sound change so that it now rhymes with yay

Yeah is indeed from yea, from Old English gea. All three were originally pronounced identically, but yea underwent a sound change so that it now rhymes with yay. Yeah is one of the few words to have retained its Old English pronunciation. https://en.wiktionary.org/wiki/yeah https://en.wiktionary.org/wiki/yeah