Established on July 31, 1789, it collected import tariffs, performed other selected border security duties, as well as conducted criminal investigations.

Responding to the urgent need for revenue following the American Revolutionary War, the First United States Congress passed and President George Washington signed the Tariff Act of July 4, 1789, which authorized the collection of duties on imported goods.

Four weeks later, on July 31, the fifth act of Congress established the United States Customs Service and its ports of entry.

For over 100 years after it was founded, the U.S. Customs Service was the primary source of funds for the entire government, paying for the country's early growth and infrastructure.

Customs Inspectors were uniformed officers at airports, seaports and land border ports of entry who inspected people and vehicles entering the U.S. for contraband and dutiable merchandise.

In the 20th century, as international trade and travel increased dramatically, the Customs Service transitioned from an administrative bureau to a federal law enforcement agency.