Where does “-heit” come from?

-heit (Middle Low German) comes from Old Saxon -hed, from Proto-West Germanic -haidu, from Proto-Germanic haiduz, from Proto-Indo-European (s)kayt-.

Ancestry of “-heit”, step by step

Step	Language	Word	Meaning
1	Old Saxon	-hed	forming nouns of condition or quality, from nouns...
2	Proto-West Germanic	-haidu	—
3	Proto-Germanic	haiduz	manner, way; personality, character; appearance
4	Proto-Indo-European	(s)kayt-	—

-heit — Etymology, Origin & Word History | Etymology Explorer