Rehnquist was born William Donald Rehnquist in Milwaukee, Wisconsin and grew up in the suburb of Shorewood. His father, William Benjamin Rehnquist, was a paper salesman; his mother, Margery Peck Rehnquist, was a translator and homemaker. Rehnquist changed his middle name to Hubbs, his grandmother's maiden name, during his high school years. His paternal grandparents emigrated from Sweden.
After the war ended, Rehnquist attended Stanford University with assistance under the provisions of the G.I. Bill. In 1948, he received both a Bachelor of Arts and a Master of Arts degree in political science. In 1950, he went to Harvard University, where he received another Master of Arts in government. He later returned to Stanford, where he graduated from the Stanford Law School in the same class as Sandra Day O'Connor, with whom he would later serve on the Supreme Court. They briefly dated at Stanford It has been said that Rehnquist graduated first in his class,probably based on the fact that he was class valedictorian during graduation ceremonies, but Stanford's official position is that the law school did not rank students in 1952.