1 Euro

Montenegro used German-designed euro-sized coinage from 2002 onward despite having no formal agreement with the European Central Bank — the country adopted the euro unilaterally, first the Deutschmark and then the euro, out of practical necessity following the collapse of the Yugoslav dinar. These pieces were never legal tender in the eurozone and were intended solely for domestic circulation, which kept mintages modest and distribution uneven across the small Adriatic state.