Krum's campaigns Simeon I's campaigns Sviatoslav's invasion of Bulgaria Byzantine conquest of Bulgaria Uprising of Peter Delyan Second Bulgarian Empire The siege of Adrianople (Bulgarian: Обсада на Одрин) in 813 was a part of the wars of the Byzantine Empire with the Bulgarian khan Krum (Byzantine-Bulgarian Wars).

It began soon after the Byzantine field army was defeated in the battle of Versinikia on 22 June.

At first the besieging force was commanded by Krum's brother[1] (whose name is not mentioned in the primary sources).

After an unsuccessful Byzantine attempt to murder him ruined all prospects for negotiations with them, Krum ravaged much of Eastern Thrace and then turned against Adrianople which was still under siege.

On Krum's orders, the population of Adrianople and the surrounding area (numbering about 10,000) was transferred to Bulgarian territory north of the Danube.