Uncertain. Has been linked to Runic แ(/โ jโ /), uncial Latin G, and even to a cursive Ancient Greekฮ(X/โ ksโ /). Snรฆdal favours the Latin origin.[1] Latin โจgโฉ was indeed used for /j/ in various medieval languages. The Gothic letter may have been invented after Wulfila.
^ Snรฆdal, Magnรบs, Gothic contact with Latin: Gotica Parisina and Wulfilaโs alphabet, in: Askedal, J.O. & Nielsen, H.F. (ed.), Early Germanic languages in contact, Amsterdam, 2015, pp. 91-108, especially 100-101.
