When Protestantism spread, it found fertile ground in different parts of what was left of the Kingdom of Hungary (this was after the Ottoman invasion). Chiefly in Transsylvania, which already had a history of widespread hereticism (bogumils, arianism), and then had many Calvinists, and then was actually the source of Unitarianism. there were more Lutherans in the Austrian-held Northern part (today Slovakia), but the Habsburg rulers' (often bloody) recatholisation efforts decreased Protestant numbers.

In today's Hungary, according to the last (2001) census, 55% called themselves Catholic, 15% Calvinist, 3% Lutheran (note though that for many this is only cultural identifier -- you had Catholic baptism, Catholic family --, not actual belief). Hungary's second-largest city Debrecen (incidentally, also Fidesz's strongest base), near the Romanian border, is their main centre.

I note one of my grandfathers was a Calvinist (who married a Catholic).

_{*Lunatic*, n.
One whose delusions are out of fashion.}

_{*Lunatic*, n.
One whose delusions are out of fashion.}