| Conflict: | Siege of Breisach |
| Partof: | the Thirty Years' War |
| Date: | 18 August – 17 December 1638 |
| Place: | Breisach, Holy Roman Empire |
| Result: | French-Weimaran victory |
| Combatant1: | Kingdom of France Weimar Army |
| Combatant2: | Holy Roman Empire Bavaria |
| Commander1: | Bernard of Saxe-Weimar Vicomte de Turenne |
| Commander2: | Johann von Götzen Federico Savelli |
| Casualties1: | 1,700 |
| Casualties2: | 4,000 |
The siege of Breisach was fought on 18 August — 17 December 1638 as part of Thirty Years' War. It ended after several unsuccessful relief attempts by Imperial forces with the surrender of the Imperial garrison to the French, commanded by Bernard of Saxe-Weimar.[1]