The fort at Pembina was attacked by a party of 200 Sioux at midnight of July 22, 1808. There were then twenty-two men bearing arms, fifty women and many children encamped in the vicinity. Alexander Henry defended the fort with the men encamped outside, nine men inside, and a mortar cannon loaded with one pound of powder and thirty balls, which had recently been added to the equipment.
At the hour of attack the Chippewas had been drinking heavily, and were generally asleep in their tents. Their arms were in the fort and the gates were closed, but when roused they clambered over the stockade and secured their arms, hurrying the women and children into the fort.
The piece [cannon] when in action was aimed in the direction where the Sioux could be plainly heard addressing their men, and no such noise as its roar had ever been heard on the Red River before. The balls clattered through the tree tops and some took effect, for the lamentations of the Sioux for their fallen comrades could be distinctly heard. For a few moments only the firing continued and the Sioux were next heard at some distance, then farther off, farther and farther. About sunrise they could be dimly discerned filing away to the southward.
Their pursuers found the stain of blood where the Sioux were first heard, and evidence of a hasty retreat. On the spot where they put on their war bonnets and adjusted their accoutrements, making ready for the assault, upwards of one hundred old shoes were found; also some scalps, remnants of leather and buffalo robes, saddle cloths, pieces of old saddles, paunches and bladders of water for their journey—and a lone grave on the prairie where one of their dead had been left. The loss at the fort was one dog killed by the Sioux shots.
Adapted from: Early history of North Dakota: essential outlines of American history, By Clement Augustus Lounsberry (1919)