Five long-range (Type IX) U-Boats sailed for the eastern seaboard shortly after the declarations of war between the US and Germany in 1941 (the crews celebrated Christmas during their transit across the Atlantic).
The number of ships that were sunk and the loss of human life that took place as a result of these five submarines remains one of the least-known Allied losses of the war.
Those were great hunting days for the U-boats. We weren't even blacking out our cities yet. They had a field day. A lot of ships sunk within sight of the coast line.