Hubert H. Humphrey was born on May 27, 1911, in Wallace, South Dakota. He left South Dakota to attend the University of Minnesota but returned to South Dakota to help manage his father's drug store early in the depression. He attended the Capitol College of Pharmacy in Denver, Colorado, and became a registered pharmacist in 1933. On September 3, 1936, Humphrey married Muriel Fay Buck in Huron, South Dakota. He returned to the University of Minnesota and earned a B.A. degree in 1939. In 1940 he earned an M.A. in political science from Louisiana State University and returned to Minneapolis to teach and pursue further graduate study, but began working for the W.P.A. (Works Progress Administration).
He moved on from there to a series of positions with wartime agencies. In 1943, he ran unsuccessfully for Mayor of Minneapolis and returned to teaching as a visiting professor at Macalester College in St. Paul. Between 1943 and 1945, Humphrey worked at a variety jobs, including teaching at Macalester, serving as a news commentator for radio station WTCN, and managing an apartment building. In 1945, he was elected Mayor of Minneapolis and served until 1948.
At the 1948 Democratic National Convention, the party platform reflected this division and contained only platitudes in favor of civil rights. The incumbent president, Harry S Truman, had already issued a detailed 10-point Civil Rights Program that called for aggressive federal action on the issue of civil rights. A diverse coalition opposed this tepid platform, including anti-communist liberals like Humphrey, Paul Douglas and John Shelley, all of whom would later become known as leading progressives in the Democratic Party. These liberals proposed adding a "minority plank" to the party platform that would commit the Democratic Party to a more aggressive opposition to racial segregation. The minority plank called for federal legislation against lynching, an end to legalized school segregation in the South, and ending job discrimination based on skin color.
Despite aggressive pressure by Truman's aides to avoid forcing the issue on the Convention floor, Humphrey chose to speak on behalf of the minority plank. In a renowned speech, Humphrey passionately told the Convention, "To those who say, my friends, to those who say, that we are rushing this issue of civil rights, I say to them we are 172 years (too) late! To those who say, this civil rights program is an infringement on states' rights, I say this: the time has arrived in America for the Democratic Party to get out of the shadow of states' rights and walk forthrightly into the bright sunshine of human rights!" Humphrey and his allies succeeded; the pro-civil-rights plank was narrowly adopted.
As a result of the Convention's vote, the Mississippi and one half of the Alabama delegation walked out of the hall. Many Southern Democrats were so enraged at this affront to their "way of life" that they formed the Dixiecrat party and nominated their own presidential candidate, Governor Strom Thurmond of South Carolina. The goal of the Dixiecrats was to take Southern states away from Truman and thus cause his defeat. The Southern Democrats reasoned that after such a defeat the national Democratic Party would never again aggressively pursue a pro-civil rights agenda. However, the move backfired. Although the strong civil rights plank adopted at the Convention cost Truman the support of the Dixiecrats, it gained him many votes from blacks in large northern cities. As a result Truman won a stunning upset victory over his Republican opponent, Thomas E. Dewey. Truman's victory demonstrated that the Democratic Party could win presidential elections without the "Solid South", and thus weakened Southern Democrats instead of strengthening their position. Pulitzer Prize-winning historian David McCullough has written that Humphrey probably did more to get Truman elected in 1948 than anyone other than Truman himself.
Minnesota elected Humphrey to the United States Senate in 1948 on the DFL ticket, unseating incumbent Republican Joseph H. Ball with 60% of the vote, and he took office on January 3, 1949. He was the first Democrat elected senator from the state of Minnesota since before the Civil War. Humphrey's father died that year, and Humphrey stopped using the "Jr." suffix on his name. He was re-elected in 1954 and 1960. His colleagues selected him as majority whip in 1961, a position he held until he left the Senate on December 29, 1964 to assume the vice presidency.
Humphrey ran for the Democratic presidential nomination twice before his election to the Vice Presidency in 1964. The first time was as Minnesota's favorite son in 1952, where he received only 26 votes on the first ballot; the second time was in 1960. In between these two presidential bids, Senator Humphrey was part of the free-for-all for the vice-presidential nomination at the 1956 Democratic National Convention, where he received 134 votes on the first ballot and 74 on the second. In 1960, Humphrey ran again for the Democratic presidential nomination against fellow Senator John F. Kennedy in the primaries. At the 1960 Democratic Convention he received 41 votes even though he was no longer an active presidential candidate. Humphrey's defeat in 1960 had a profound influence on his thinking; after the primaries he told friends that, as a relatively poor man in politics, he was unlikely to ever become President unless he served as Vice-President first.
Humphrey believed that only in this way could he raise the funds and nationwide organization and visibility he would need to win the Democratic nomination. As such, as the 1964 presidential campaign began Humphrey made clear his interest in becoming President Lyndon Johnson's running mate. At the 1964 Democratic National Convention, Johnson kept the three likely vice presidential candidates, Connecticut Senator Thomas Dodd, fellow Minnesota Senator Eugene McCarthy, and Humphrey, as well as the rest of the nation in suspense before announcing Humphrey as his running-mate with much fanfare, praising Humphrey's qualifications for a considerable amount of time before announcing his name.
Humphrey took office on January 20, 1965. As Vice President, Humphrey was controversial for his complete and vocal loyalty to Johnson and the policies of the Johnson Administration, even as many of Humphrey's liberal admirers opposed Johnson with increasing fervor with respect to Johnson's policies during the war in Vietnam. Many of Humphrey's liberal friends and allies over the years abandoned him because of his refusal to publicly criticize Johnson's Vietnam War policies. Humphrey's critics later learned that Johnson had threatened Humphrey — Johnson told Humphrey that if he publicly opposed his Administration's Vietnam War policy, he would destroy Humphrey's chances to become President by opposing his nomination at the next Democratic Convention. However, Humphrey's critics were vocal and persistent: even his nickname, the Happy Warrior, was used against him. The nickname referred not to his military hawkishness but rather to his crusading for social welfare and civil rights programs.