Duke Dox of Transylvania (827-) was the Duke of Transylvania and Prince of the First Bulgarian Empire, as well as the heir to the County of Szekelyfold.
Biography[]
Dox was the son of King Presian of Bulgaria, and was an Orthodox Christian from the Bulgarian House of Balgarsko. Dox was the brother of King Boris I of Bulgaria and Duke Gavril of Moldau, two members of the Bulgarian nobility. Dox was enfeoffed as the Duke of Transylvania (present-day Romania) by his father before he died, and he was also a prince of Bulgaria and heir to the County of Szekelyfold.