In Germany, he is an Easter hare and I assume he crossed the Atlantic with Germans who emigrated to the U.S from 1848 onwards. There he tranmogrified into an Easter bunny,
He was totally unknown in my childhood both in Scotland and in Denmark, the two countries where I grew up.
As far as I know, this tendency not to let children believe in Santa Claus is part of the "never lie to children" idea.
Certainly, children learn by example, so not telling them lies is fine, but , but ...
...if Santa Claus is a no go, what happens to the first great love of my life? I was two when I fell hopelessly in love with Puss in Boots.
If Santa is a lie, then surely both Puss in Boots, Sleeping Beauty, Cinderella and hordes of other beloved "inhabitants"of our childhood have to go too?