Today an Easter greeting from my aunt Kerstin prompted me to look into something I've long idly wondered about, and that’s why the Swedish for Easter is Påsk (pronounced Posk). I was led to the following information from Wikipedia. The 8th century English scholar Bede, describing the state of affairs in England a couple of hundred years before his own day, stated that the Anglo-Saxon word for April was Easter Month (Ēosturmōnath) during which feasts were held in honour of the goddess Ēostre. All this had died out by Bede’s time, replaced by the Christian "Paschal month".
The word Paschal is derived from the Hebrew word for Passover, Pesach. The dates of the two festivals, Easter and Passover, normally coincide within five or fewer days, but about every tenth year they go adrift by a whole month. There's a long history of debates as to how Easter should be calculated which I won’t go into here.
What about Easter in other European languages? In the Romance languages, as in the Scandinavian languages, it's derived from Hebrew (French Pâques, Italian Pasqua). But in German it's Ostern, the same root as English.
The goddess Ēostre is a form of the widely attested Indo-European dawn goddess (hence East), and there are theories connecting Ēostre with records of Germanic Easter customs including hares and eggs.
An invention of Bede's?
Here's a curious note to end on. The evidence for the Anglo-Saxon goddess whose name gives rise to "Easter" has not, it seems, been universally accepted, and some scholars have proposed that Ēostre may have meant "the month of opening" or that the name Easter may have arisen from the designation of Easter Week in Latin as in albis. (Not quite sure how you get from in albis to Easter.)
It's even possible it was Bede who invented the Anglo-Saxon goddess Ēostre. But whether he did or didn't, it seems odd that the English church should have chosen the name Easter, thereby connecting their principal festival with either a pagan goddess or a supposed pagan goddess.
My £10 donation to Wikipedia last month was money well spent, but there's more to find out yet.