The following year the United States unhappily declared war against Great Britain. The American government had previously laid an embargo upon all their national ships and vessels during a space of ninety days, so that when war broke out on the 18th of June a large number of fast-sailing-vessels of all sizes were ready to issue forth as privateers; while Commodore Rogers, in command of the squadron, consisting of the President,United States, and Congress frigates, and two brigs of war, sailed in hopes of capturing a fleet of above 100 homeward-bound Jamaica men, known to be off the coast, under the convoy of a single frigate and brig. Fortunately for the merchant-vessels, Commodore Rogers discovered the British frigate Belvidera, of 36 guns, 18-pounders, commanded by Captain Byron, standing towards him. Captain Byron, having ascertained the character of the American squadron, tacked and made sail, not so much to escape as to lead the enemy to a distance from their expected prey. By consummate seamanship and gallantry, he kept them employed, carrying on a spirited action with his two long 18-pounders run through his stern-ports, and the two 32-pounder carronades on his quarter-deck, greatly galling the President, and afterwards the Congress, when that frigate got near enough to open her fire. So successfully did he manoeuvre, that after leading his pursuers a long chase, he escaped from them and got into Halifax. The Belvidera lost altogether 3 killed and 22 wounded. The President, which was cut up in her rigging, lost 2 midshipmen and a marine killed, and 22 officers and men wounded; while the Jamaica convoy reached England in safety.
The war between England and her former dependencies had now commenced in earnest. Since their independence, the United States had taken pains to construct an efficient, though small navy. Aware that it would be useless to attempt building line-of-battle ships to compete with the fleets of Europe, they had turned their attention to the construction of frigates, to act as ocean cruisers, of a size and armament capable of contending successfully with any possessed by England, or indeed any other maritime power. The result proved the wisdom and forethought of their naval authorities. Their most famed frigates were the Constitution, the United States, and President. The other two were of the same size and force as the latter vessel. The President measured 1533 tons: her sides and bulwarks were thicker, and her spars and rigging stouter than those of a British 74-gun ship, while she sailed admirably. She was pierced for 56 guns, but only mounted 52, of which 32 were long 24-pounders, and 20 42-pounders, her complement being 480 men. The other two mounted 54 guns, and the Constitution carried 32 instead of 42-pounder carronades.