Learn German: Silvester ist im Dezember. - New Year's Eve is in December.

To say that something happens in a certain month, German always uses im. This is a combination of in + dem (meaning 'in the'). Since all months are masculine (like der Dezember), answering the question 'when?' puts the word for 'the' into the dative case, changing der to dem.

Where does the word Silvester come from?

Silvester is the German name for New Year's Eve (December 31st). It is named after Pope Sylvester I, whose traditional saint's day falls on the very last day of the year.

Do month names always start with a capital letter in German?

Yes! All twelve months, from Januar to Dezember, are capitalized. This is because every single noun in German gets a capital letter, which also applies to holidays like Silvester.

Is there a gender or article for Silvester?

It is technically neuter (das Silvester), but you will almost always see it used without an article. Just like in English, we say 'New Year's Eve is...', rather than 'The New Year's Eve is...'.