The perun (Serbian Cyrillic: Перун, older spelling: Перунъ) was the currency that was planned for introduction in Montenegro by Petar II Petrović Njegoš in 1851. However, he died the same year, and Montenegro remained without a currency until the 1906 introduction of the perper by Nicholas I of Montenegro.
It was named after Perun, whom Njegoš considered to be the supreme god of Slavic mythology. If introduced, one Perun would have had equal value to two thalers. Montenegro later used the Austrian currencies until 1906 when Montenegro started using the Montenegrin perper.