Hostilities were commenced in Upper Canada. No sooner had General Brocke learned that war was proclaimed, than he conceived a project of attack. He did not mean to penetrate into the enemy's country, but for the better protection of his own, to secure the enemy's outposts. On the 26th of June, he sent orders to Captain Roberts, who was at St. Joseph's, a small post, or block house, situated on an island in Lake Huron, maintained by thirty soldiers of the line and two artillerymen, in charge of a serjeant of that corps, under the command of the gallant captain, to attack Michillimackinac, an American fort defended by seventy-five men, also under the command of a captain. He was further instructed to retreat upon St. Mary's, one of the trading posts belonging to the North West Fur Company, in the event of St. Joseph's being attacked by the Americans. General Brocke's instructions reached Captain Roberts on the eighth of July, and he lost no time in carrying the first part of them into execution. Communicating the design, the execution of which he had been entrusted with, to Mr. Pothier, in charge of the Company's Post, at St. Joseph's, that gentleman patriotically tendered his services. Mr. Pothier, attended by about a hundred and sixty voyageurs, the greater part of whom were armed with muskets and fowling pieces, joined Captain Roberts with his detachment of three artillerymen and thirty soldiers of the line, and in a flotilla of boats and canoes, accompanied by the North West Company's brig _Caledonia_, laden with stores and provisions, a descent was made upon Michillimackinac. They arrived at the enemy's fort, without having met with the slightest opposition, and summoned it to surrender. The officer in command of the American fort at once complied. He had indeed received no certain information that war had been declared. Very shortly afterwards two vessels, laden with furs, came into the harbour, ignorant of the capture of the fort, and were taken possession of, though subsequently restored to their proprietors, by Major-General DeRottenburgh, the President of the Board of Claims. Unimportant as this achievement was, it yet had the effect of establishing confidence in Upper Canada. It had an excellent effect upon the Indian tribes, with whose aid the struggle with the Americans, was afterwards efficiently maintained.