The ensign is the official flag of U.S. Customs and Border Protection. Its origin dates to 1799. It was originally employed to identify U.S. revenue cutters and customs vessels and their power to enforce federal laws and regulations. The U.S. Congress mandated its use so that these ships would be distinguished from other vessels.
A Circular Letter, issued by Treasury Secretary Oliver Wolcott and dated August 1, 1799, outlined the basic elements of the ensign’s design. The circular directed that the ensign should contain "sixteen perpendicular stripes, alternate red and white, the Union of the Ensign to be the Arms of the United States, in dark blue, on a white field."
In the 19th Century, the ensign as a symbol of federal authority was extended to federal buildings. Customs collectors were flying the ensign over the U.S. customhouses by the 1850s. The author and surveyor of customs Nathaniel Hawthorne refers to this practice in the first chapter of his novel The Scarlet Letter. This chapter was titled Customhouse. The practice was codified a half-century later, when in 1874, Treasury Secretary William A. Richardson required that during business hours, the ensign was to be flown alongside the American flag over all customhouses.
The design of the ensign has been modified across the years. The design was standardized in the 1860s when the Treasury Department took control of production and issuance. The ensign’s current design was set in 1952 under a flag identification project authorized by President Harry S. Truman. The heraldic branch of the U.S. Army provided guidance in the redesign of the ensign. On the historic Customs ensign, the scroll was absent from the eagle’s beak, its talon held only three arrows instead of thirteen, and the stars were arranged above the eagle in an arc. Based on the guidance of the heraldic branch the customs ensign was altered to display the arms of the U.S.
A modified version of the ensign is the official flag of the Coast Guard. President William Howard Taft established the distinction between the two ensigns in an Executive Order on June 7, 1910. The order stated that "the flag now used on vessels of the Revenue Cutter Service be marked by the distinctive emblem of that Service, in blue and white . . . over the center of the seventh vertical red stripe." In 1927, Secretary of the Treasury, Andrew Mellon, ordered the emblem changed to the official seal of the U.S. Coast Guard.
Across three centuries, the ensign has witnessed American history. For many legacy Customs and CBP employees, it has also become an unofficial symbol of the endurance of the federal government against threats. It flew over the New York customhouse on September 11, 2001, and an ensign was recovered from the debris of ground zero. This tattered ensign became an important artifact for the U.S. Customs Service, and when the Department of Homeland Security was created in 2003, the tattered ensign from 9/11 was transferred to CBP.
Thus, the ensign became emblematic of both the endurance and the continuity of government. And today, the ensign and its U.S. Coast Guard variant continue to represent federal authority, as well as the work of the Department of Homeland Security to safeguard the nation against threats.