If you are looking for costumes ideas for an European country, this is where you will find them. Ideal if you are attending, or hosting, a Eurovision party.
This section splits down further into actual countries- just look at the categories on the left.
Why not allocate guests a specific country and ask them to bring some food and / or drink that is associated with that country?
Put up European country flags to decorate your room and play various National Anthems during the evening. If guests know it is their National Anthem (what they have dressed up as) they get a prize, or if they don’t, they get a forfeit (may be more fun!!)