The Judiciary Act of 1789 established a federal court system. It is also known as the 1789 Judiciary Act, officially titled, “An Act to Establish the Judicial Courts of the United States. The Act basically established the federal court system of the United States of America because it was only sketched in general terms in the U.S. Constitution.
The act divided the federal court system into a three-part judiciary --- district courts, circuit courts, and Supreme Court. It also outlined the exact roles of these courts in the system.