The office of Alien Property Custodian was created by the Trading with the Enemy Act of October 6, 1917. According to the act, the right to seize enemy property was vested in the president, which was then delegated to the Alien Property Custodian. This collection consists of nine volumes, fifty-eight booklets, and foldouts concerning U.S. patents vested in the Alien Property Custodian (1943-1946). The materials specifically deal with mechanical and electrical patents, as well as chemical patents.

Pierre Samuel du Pont de Nemours (1739-1817) was a French political economist, writer, publisher, and public administrator. In 1802, he held various government posts under Napoleon Bonaparte (1769-1821). In 1803, he aided President Thomas Jefferson (1743–1826) in negotiations for the Louisiana Purchase, a land deal transferring ownership of more than 530 million acres of territory to the United States from France. The principal item of this collection is a letter to James Monroe, minister plenipotentiary to negotiate the Louisiana Purchase, dated May 7, 1803. The letter is encased in a leather bound portfolio containing the original handwritten French letter, a typed English translation, and three other items.