Why did the federalist party lose support after the war of 1812?

It died off because of two reasons, the war of 1812 and because it seemed unpatriotic when holding the hartford convention. i hope this . 

The federalist party died after the war of 1812. it died it off for two reasons: because of the war of 1812, and because it seemed unpatriotic when holding the hartford convention. the federalists had opposed the war from the beginning and this was an unpopular opinion that didn't have much support.

What war are you specifically talking about?