You might try to figure out why Мирча got IWNЬ written on that picture.
I would suspect that it is his name and title. Slavic script coins got something like ‘Iω MIRCEA VOEVODA’
You could also try finding Bulgarian reference book in your library.
Octavian Luchian, George Buzdugan, Constantin C. Oprescu, Emil Condurachi - Monede şi bancnote româneşti, 1977.
On the painting its written IωNЬ and Iω is the shortcut for it, its kind of a title but in reality it only means “me” so: “Me, voivode Mircea” is the usual lettering, but on this coin its different from what im used to.
I am using the monede si bancnote romanesti catalogue but it dosent say anything about the translation, and also this type of the coin is written in latin letters, the type Ib is cyrillic and Ic had latin on one side and cyrillic on the other. The coins with latin lettering dont usually have Iω on them, the only one i have came across was this one, but its still far from IWAN: N#115844
