Where does “-ь” come from?

-ь (Old East Slavic) comes from Proto-Slavic -ь, from Proto-Indo-European -is — Forms nouns from verbs.

Ancestry of “-ь”, step by step

StepLanguageWordMeaning
1Proto-Slavic-ьForms nouns; From adjectives; From participles
2Proto-Indo-European-isForms nouns from verbs

Words derived from “-ь”

Every word from Proto-Indo-European -is →Every word from Proto-Slavic -ь →