Where does “Katariina” come from?

Katariina (Finnish) comes from Swedish Katarina, from Medieval Latin Catharīna, from Latin Ecaterina, from Ancient Greek Αἰκατερίνη, from Ancient Greek Ἑκάτη, from Ancient Greek ἑκάς, from Ancient Greek ἕ, from Proto-Hellenic hwe — self.

Katariina (Finnish): Catherine