| Conflict: | Crossing Kvarken |
| Partof: | the Finnish War |
| Date: | 8–10 March 1809 |
| Place: | Kvarken, Gulf of Bothnia |
| Territory: | Swedish are evacuated Västerbotten |
| Result: | Russian victory[1] |
| Combatant1: | Sweden |
| Combatant2: | Russian Empire |
| Commander1: | Georg Carl von Döbeln |
| Commander2: | Michael Andreas Barclay de Tolly |
| Strength1: | 1,000 |
| Strength2: | 3,000 |
| Casualties1: | Unknown |
| Casualties2: | ~200 |
The crossing the Gulf of Bothnia, specifically Kvarken (Swedish: korsar Bottenviken; Russian: Переход через Кваркен), was a march of Russians through Kvarken, Gulf of Bothnia, to the territory of Sweden at Umeå. It was during the Finnish War in March 1809.[2]
For the whole winter, the operation was in preparation. In the middle of February 1809 followed the appointment of Lieutenant General Michael Andreas Barclay de Tolly as commander of the Vasa Corps, who pushed forward preparations for the campaign. On March 6 an order was read at the assembly point, in which Barclay, without concealing the labours to come, expressed his confidence that "for Russian soldiers the impossible does not exist."
The march began on March 8, 1809, and, according to its idea, was a unique event in world history. In the cold more than -15 degrees, Russians were walking across the icy desert towards Umeå. In front of the Swedish coast, they burned two merchant ships to keep warm. The troops had to abandon their artillery halfway due to the inability to quickly transfer it across the ice. They were opposed by a detachment in Umeå numbering no more than 1,000 people. Seeing the numerical superiority of the Russians, the Swedes tried to let go, but their rearguard units were overtaken and defeated, for example, a column under the command of engaged 3 companies of Swedes and forced them to retreat, taking 36 prisoners including 1 officer. On March 10, Barclay de Tolly entered Umeå. The Swedish troops there surrendered and promised to surrender all Västerbotten.
Alexander I personally presented individual to each participant of the campaign.[3]