Dalmtian

From a previous post I noticed that reference was made to a language
called Dalmation and that it was a Romance language. Forgive my
ignorance but I was not aware that there had been a Dalmatian language.
I assume it was spoken in what is now coastal Croatia. How widely was
it spoken and when did it die out? From the previous post I assume that
it resembled Romanian. Is this so?