The 1926 Series refers to a specific set of banknotes issued by the United States Treasury. These notes were part of the larger series of currency produced during the 1920s and are notable for their distinctive designs and historical significance. The series includes various denominations, featuring prominent figures such as George Washington and Abraham Lincoln. The 1926 Series is particularly recognized for its use of intricate artwork and security features that were advanced for the time. Collectors often seek these notes due to their rarity and the unique characteristics that reflect the economic conditions of the era.