Why, in some countries, do they say Happy Christmas, while in other countries the expression is Merry Christmas?

"Happy Christmas" is apparently more common in the U.K. and Ireland, possibly owing to the fact that "merry" can connote overindulgence in alcohol.

Scroll down to "History of the Phrase":


https://en.wikipedia.org/wiki/Holiday_Greetings

[Link verified on August 22, 2016 by shuehorn]

The alternative "Happy Christmas" gained wide usage in the late 19th century, and is still common in the United Kingdom and Ireland. One reason may be the alternative meaning, still current there, of "merry" as "tipsy" or "drunk". Queen Elizabeth II is said to prefer "Happy Christmas" for this reason[3]. In American poet Clement Moore's "A Visit from St. Nicholas" (1823), the final line, originally written as "Happy Christmas to all, and to all a good night", has been changed in many editions to "Merry Christmas to all", perhaps indicating the relative popularity of the phrases in the United States.
https://en.wikipedia.org/wiki/Holiday_Greetings#Merry.2FHappy_Christmas

[Link verified on August 22, 2016 by shuehorn]

There is quite a bit of "hesitation" in other languages too. In Dutch e.g. "Vrolijk Kerstmis" (Merry) alternates with "Zalig Kerstfeest" (Blessed). Some religious-minded people seem to avoid "vrolijk" because it does not emphasize the religious meaning.

Zalig Kerstmis in heel veel talen / Katholiek - RK Kerk - Isidorusweb
Wondering if anyone says "Joyful Christmas", which would be closer to French "Joyeux Noël". In a number of languages they stick to the simplicity of "Good Christmas". "

God Jul" (Swedish);"Gute Vaihnaten" (Yiddish); "Buon natale" (Italian). South-African Dutch("Afrikaans")has "Geseendes", which would translate as "Blessed Christmas". Are "Happy"/"Merry" really the only possible phrases in English?