Iisakki

Anyone who is wondering about the prevalence of names in Finland can check them from the Finnish Population Centre's online name service, since they helpfully provide an English version.

---

http://verkkopalvelu.vrk.fi/Nimipalvelu/default.asp?L=3

---

There we find, for example, that in 2010-2016, 780 boys have been named Iisakki as their first or second name.

I don't think anyone has ever named their son this in Finland. I could be wrong, but the name is certainly very old-fashioned, so it wouldn't be used today. It has a silly sound to it, and I'm pretty sure even the Biblical character has always been called Iisak in the Finnish translations of the Bible.