Establishment of the U.S. Customs Service
The establishment of the U.S. Customs Service came with the act of July 31, 1789, by which the first US Congress created 59 customs collection districts and officers to collect the duties set by the Tariff Act of July 4, 1789.
What happened and why it matters
The 1789 customs laws created the agency that still decides when imported goods are released, and for much of the 19th century customs duties were the federal government's main source of revenue. The Tariff Act of July 4 set duties on imports, and the act of July 31 set up 59 collection districts staffed by collectors, naval officers, and surveyors. The service later became the U.S. Customs Service and, in 2003, part of U.S. Customs and Border Protection. Every entry an importer files today, with its tariff classification, declared value, and duty payment, descends from that first system.