In anticipation of a raid on the South Atlantic by the German Navy, a United States Naval task force commanded by Rear Admiral Jonas H. Ingram, patrolled the waters of the mid-Atlantic beginning in mid-June 1941. The task force included the USS Memphis, the Milwaukee, Cincinnati, and the Omaha (all Light Cruisers), the Somers (from Destroyer Squadron 9) and a few auxiliary ships. By August 1, 1941 the task force had been ordered to operate as if in a time of war.

On November 4, 1941, the British oiler Owlen reported being attacked by a German ship. The US Naval Task force headed south to help search for the German ship or any other signs of the attack. The search continued throughout the 4th and 5th of November 1941, but no signs of the attack were found.
The US Naval task force began to head to Recife, Brazil in order to refuel. While en route, the Omaha sighted a suspicious vessel. The ship was flying the American flag and claimed to be the U.S. freighter Willmoto from Philadelphia. However, as the Omaha approached, the Willmoto tried to evade her. When the Omaha dispatched a boarding party, crewmen on the Willmoto began to take to life boats. As the boarding party reached the Willmoto they heard explosions coming from the ship. The Germans had apparently set off internal charges in an attempt to skuttle the ship. Once aboard, the US crew saved the ship and discovered her real name was the Odenwald. The Odenwald was a blockade runner transporting rubber from Japan to Germany.

The Odenwald was successfully escorted to San Juan, Puerto Rico on November 11, 1941. One of the crew aboard the Odenwald was actually a member of the German Navy, named Helmut Ruge. Helmut Ruge was serving as a Radio Operator aboard the Odenwald. Captain Chandler, Captain of the Omaha, was unsure of the legality of taking Prisoners of War, as the United States was still declared neutral. He reported the Odenwald was suspected of being involved in the slave trade. A tactic which he knew was successful 100 years earlier.

In a reported released March 12, 1942 by the Office of the Chief of Naval Operations, Helmut Ruge was officially declared “first German prisoner of war captured by the United States” The capture of the Odenwald occurred 1 month prior to the United States Declaration of War on Japan.