How many justices served on the original U.S. Supreme Court in 1789? The answer is six.
The Judiciary Act of 1789 established the Court with one Chief Justice and five associate justices. President George Washington nominated the first group, including John Jay as Chief Justice and figures such as William Cushing, James Wilson, and John Blair Jr. The Court reached its initial six-member complement when James Iredell joined in 1790 after Robert H. Harrison declined the appointment.
The Constitution created a Supreme Court but did not specify how many justices it must contain. Congress has therefore changed the Court’s size several times. It expanded to seven in 1807, nine in 1837, and ten in 1863, before returning to nine in 1869.
The familiar number nine is not the original constitutional number; it is the modern statutory arrangement. Another historical detail often missed is that the early justices performed circuit-riding duties, traveling to hear cases in federal judicial districts rather than working only in Washington.