Sweden
In Sweden, crossbows are considered equivalent to firearms, and possession requires a license (Vapenlag (1996:67)). Hunting with crossbows is not allowed. Swedish law dictates that any weapon that stores it's energy, ie weapons with a firing mechanism, that produces more than 10 joules at the muzzle are illegal without licence. Thus very weak crossbows are sold in toy stores as well as low powered air rifles (not sold to minors) while sale or possession of normal bows of any strength are not regulated.
Read more about this topic: Laws On Crossbows