Flag of Vidin/Bulgaria as Shown in the Book of All Kingdoms
The following shown above is the flag of "Vecina", identified as the Bulgarian city of Vidin, and describes that this is the flag of Vidin before it fell to the Ottoman Empire after the death of the author.
Data
Proportions:
6:5
Use:
National Flag of the Principality of Vidin
Design:
A white banner of a square white cross with a red background.
Date Used:
Circa 1440
Sources