BOTH AT THE TIME AND SINCE, events seem to have conspired to disguise the impact of the British commercial and naval blockades of the United States, implemented after its declaration of war on Britain in June 1812. Yet, in thirty two months of war, a British naval blockade was to contain most of the American navy such that it was unable to prevent a British maritime commercial blockade. This, in turn, bankrupted a United States government heavily dependent on customs revenue and credit, and led to the abandonment of its original war aims in peace negotiations.

When news of Madison's declaration of war was finally confirmed in London on 30 July 1812 the British Cabinet's priority was to use the occasion of Warren's arrival in North America to find a diplomatic solution to this additional problem while still at war with France. It was posed by an American refusal to accept the restraints on neutral trade made necessary by Britain's need to blockade France, which some Americans had seen as a trading opportunity. The Royal Navy's efforts to recover apparently British seamen from neutral vessels had exacerbated the problem. Should Warren's diplomatic efforts fail, naval and commercial blockades of the United States would be added to the world-wide commitments of a hugely expensive and already overstretched Royal Navy, now in the ninth year of its renewed war with Napoleon.