Second Battle of Varna

The Second Battle of Varna was a confrontation which took place during the Great Mediterranean War, in Part 2 of Episode X of Varna (the series). The League of Varna had only been formed a few days before the battle, and the next day, November 11th, marked the end of the Third Bulgarian Empire.
(This battle is not to be confused with the opening scene of the series, which was the First Battle of Varna.)