Civil Flag of Serbia & State Flag of the Principality of Serbia

Flag of the Principality of Serbia (1815-1882). It also serves as the civil flag of both the Kingdom of Serbia (1882-1918) and the Republic of Serbia (adopted in 2004).

Original Flag:
https://upload.wikimedia.org/wikipedia/commons/thumb/1/11/Civil_Flag_of_Serbia.svg/640px-Civil_Flag_of_Serbia.svg.png