This President Appointed The Most Supreme Court Justices
You may be surprised to know that the number of justices on the Supreme Court isn't etched in stone (or to be more specific, laid out in the Constitution). As KSL reports, the nation's founding document only specifies that the country is to have a Supreme Court; it does not specify how many justices the court is supposed to have. Indeed, at times throughout the nation's history, the number of justices has been seen as a political tool to be used as the president and/or legislative branch deem necessary. For example, in the beginning, the number was set at six via the Judiciary Act of 1789, per the Library of Congress. Over the centuries, that number has changed a couple of times, but since 1869, it's stood at nine.
The Constitution also says that the president has the authority to appoint justices, who must be then confirmed by the Senate. As such, perhaps the president who appointed the most Supreme Court justices isn't very surprising.
George Washington appointed the most Supreme Court justices
As the first President of the United States (under the current Constitution), George Washington was tasked with filling the Supreme Court, as History notes. During his two terms, he appointed 11 men to the court, per History, while George Washington's Mount Vernon puts that number at 10. The first full session of the newly-created Supreme Court took place on Tuesday, February 2, 1790, with John Jay serving as Chief Justice, and James Wilson, William Cushing, John Blair, John Rutledge, and James Iredell serving as Associate Justices.
After Washington, the president to make the most nominations to the Supreme Court was Franklin Roosevelt, who made nine. John Tyler similarly made nine nominations to the Court, but only one managed to be confirmed by the Senate. Four presidents — Andrew Johnson, William Henry Harrison, Zachary Taylor, and Jimmy Carter — made zero Supreme Court appointments.
In total, the 45 men who have served as president have made 160 nominations to the Supreme Court, with 124 of those having been confirmed by the Senate.