The first female U.S. Supreme Court Justice was Sandra Day O'Connor, who took her seat on September 25, 1981. Appointed by President Ronald Reagan, she broke significant ground, becoming the first woman to serve on the nation's highest court. O'Connor's appointment symbolized progress in promoting gender equality within government institutions, highlighting women's capabilities in positions of power. During her tenure, she played a critical role in many high-profile cases and was known for her moderate and pragmatic approach to decision-making. Her presence on the court has inspired generations of women to pursue careers in law and politics.