French medal for Serbian prisoners-of-war

This is a French medal to commemorate Serbian prisoners-of-war. One one side is an image of, on the left, King Peter, and his son, the Prince Regent Alexander. French versions of their names appear, respectively, as 'Pierre I' and 'Alexandre'. Beneath this is the bilingual, French-Serbian text 'GLORIEUX DEFENSEURS DE LA LIBERTE SERBE' and, in Cyrillic 'СЛАВНИ ЗАТОЦНИЦИ СРПСКЕ СЛОБОДЕ' (translating…