SHE HAD NO army behind her. The law was against her. Only a few people knew her name. But Rosa Parks's individual act of courage and determination on Dec. 1, 1955, in Montgomery, Ala., ultimately changed a way of life, moving the nation closer to fulfilling America's founding principles, rooted in equality, liberty and the intrinsic value of every person.

Mrs. Parks didn't have such far-reaching goals in mind when she decided not to give up her bus seat to a white man on that December evening 50 years ago. She was, in her own words, "tired of giving in" to a system of legal and social indignities that dehumanized black people, robbing them of dignity and self-respect. Her bold action and subsequent arrest ignited a protest movement and touched individual consciences far beyond the city where she had taken her stand. For sparking the struggle that ultimately transformed the nation, a grateful America honors Rosa Parks, who died Monday night at 92.

History has already judged Mrs. Parks kindly. She entered the later years of her life as a holder of the federal government's highest award, the Congressional Gold Medal. She was awarded the Presidential Medal of Freedom, America's highest civilian award, and dozens of colleges and universities recognized her with honorary doctorates. Rosa Parks's place of honor in U.S. history is as well deserved as it is irrevocable.

But it was not always this way. A Montgomery court found her guilty. Local and state leaders in Alabama, rather than rushing to her defense out of a sense of embarrassment and regret, instead moved heaven and earth to keep segregation laws on the books. Mrs. Parks was rewarded for her efforts with telephoned death threats and firebombings of her supporters' houses. She and her husband lost their jobs. It took months of public protests, a 381-day bus boycott and ultimately a decision by the U.S. Supreme Court to desegregate public transportation in Montgomery. Congress stood by and did nothing. So did, it must be noted, Alabama's white majority. It was Rosa Parks's bravery, and the movement it fueled -- led by the Rev. Martin Luther King Jr. -- that helped change where and how Americans worked, lived and studied across the country.

A single act, a bold stroke, by a dignified African American 50 years ago dramatically altered the course of American history. Rosa Parks is a name for the ages.