| Partof: | Second Northern War / Russo-Swedish War (1656–1658) |
| Conflict: | Siege of Dyneburg |
| Place: | Dyneburg |
| Coordinates: | 55.8833°N 26.5°W |
| Map Type: | Latvia |
| Map Relief: | yes |
| Date: | 18–31 July 1656 |
| Result: | Russian victory |
| Combatant1: | Swedish Empire |
| Combatant2: | Tsardom of Russia |
| Commander1: | Johan Willichman |
| Commander2: | Aleksey Mikhailovich |
| Strength1: | Unknown |
| Strength2: | 3,400[1] |
| Casualties1: | Unknown |
| Casualties2: | Entire garrison killed |
| Width: | 315 |
| Territory: | Dyneburg is captured by the Russians |
| Units2: | Unknown |
| Units1: | Dyneburg garrison |
The siege of Dyneburg by the Russian Army under Tsar Alexei Mikhailovich was one of the first events of the Russo-Swedish War (1656–1658), a theater of the Second Northern War.
The siege began on 18 July 1656. One night in early August, the Russian bombardment caused a fire in the grain reserves of the stronghold. Consequently, some of the garrison had to leave the defences to begin putting it down. The Russians took advantage by immediately storming the fortifications and after a two hour fight, secured a victory. The commandant of the fort, Johan Willichman, took the Swedish flag with him and jumped into the fire. The rest of the defenders as well as all males present in the stronghold were slaughtered. [2]
After capturing Dyneburg (Dünaburg, Daugavpils), Tsar Alexei Mikhailovich ordered the building of an Eastern Orthodox Church and the renaming of the city as Borisoglebsk. The capture of Dynaburg was followed by the capture of Kokenhusen.