Corbis California is celebrating the first Fred Korematsu Day on Jan. 30, 2011, to honor the Japanese-American activist, pictured in 1983

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He had just changed his name and undergone plastic surgery to alter his eyes. All he wanted was to be left alone.

On May 30, 1942, Fred Korematsu was waiting for his girlfriend on a street corner in San Leandro, Calif., a small city near San Francisco. That day was just like any other day, except that Japan had attacked Pearl Harbor six months earlier, and anti-Japanese sentiment had reached a frenzy in the U.S. Korematsu, an American-born citizen of Japanese descent, was living in hiding. On Feb. 19, President Franklin Roosevelt had issued Executive Order 9066, mandating the mass roundup and incarceration of 120,000 Japanese Americans on the West Coast. Korematsu's family had already abandoned their home and flower-nursery business in order to report to the camps. Fred, a 23-year-old shipyard welder, chose to remain behind and take his chances.

But instead of his girlfriend, police officers showed up. By that time, it was illegal for Japanese Americans on the West Coast to be freely walking down the street. A local newspaper headline read "Jap spy arrested in San Leandro." Within three months, Korematsu was convicted in a federal court of violating military orders, placed on probation and sent to the Tanforan Assembly Center in San Bruno, Calif., one of several horse-racing tracks that had been hastily converted to house thousands of Japanese Americans while 10 more permanent camps were under construction. Soon, the family was sent to an incarceration camp in the middle of a Utah desert.

Frustrated, Korematsu decided not to give up. With the help of the Northern California chapter of the American Civil Liberties Union, he decided to challenge his case all the way to the Supreme Court. Worried that dissent might worsen an already dire situation, the Japanese-American community did not support him. While waiting for the verdict in the Utah camp, Korematsu had become a pariah in his own community. In December 1944, the Supreme Court voted in a 6-3 decision against Korematsu, arguing that the incarceration was a military necessity and  amazingly  that it did not have to do with race. (See the top 10 landmark Supreme Court cases.)

While some camps began closing in early 1945, the last one operated well into 1946. Upon release, each prisoner was given just $25 to help them resume their lives. Korematsu married and had children, but was forced to live with a disloyalty conviction on his record, a black stain that hampered his ability to find full-time work as an industrial draftsman. Worried that his children's Japanese-American heritage might someday harm them, too, Korematsu kept silent about his past. His own daughter didn't find out about her father's Supreme Court case until high school, when a friend mentioned it in a book report.

Then, in 1983, nearly four decades after Korematsu's failed Supreme Court challenge, a legal historian named Peter Irons contacted him. While conducting research in government archives, Irons found World War IIera documents from multiple federal intelligence agencies clearly acknowledging that Japanese Americans posed no military threat to the U.S. These documents had been intentionally hidden from the Supreme Court during Korematsu's 1944 trial. Korematsu had finally found a way to reopen his case  on the basis of government misconduct. On Nov. 10, 1983, a judge in a federal court in San Francisco overturned his conviction. The crowd in the courtroom, many of whom were former camp prisoners, burst into tears.

After a lifetime of activism, including work on the Japanese-American redress movement and friend-of-the-court briefs on behalf of Muslim detainees in U.S. military prisons, Korematsu died in 2005 at the age of 86. Since then, three schools in California have been named after him, and in September 2010, California passed the Fred Korematsu Day of Civil Liberties and the Constitution bill, creating the first day in U.S. history to be named after an Asian American. Starting this year, on Jan. 30 of each year, schools are encouraged to teach Korematsu's story and why it remains so relevant today. (Read TIME's obituary for Korematsu.)

This Jan. 30, the Korematsu Institute, a nonprofit program co-founded by Korematsu's daughter and the Asian Law Caucus, a San Franciscobased civil rights organization, is sponsoring the first Fred Korematsu Day celebration. The event, to be held at the University of California, Berkeley, will feature the Rev. Jesse Jackson and a video tribute from Representative Keith Ellison, a Democrat from Minnesota, the first Muslim elected to Congress. Earlier this month, the Institute also shipped hundreds of Korematsu teaching kits to K-12 teachers around California.

We've already seen a preview of how Korematsu's story can inspire even the youngest students. Every Monday morning, at the Fred T. Korematsu Discovery Academy in East Oakland, Calif., a low-income neighborhood made up of mostly African-American and Latino families, students recite the following creed: "Korematsu! We stand up for what is right!" As Americans' constitutional rights are threatened again and again, it's a mantra that could make a world of difference.

Ling Woo Liu is the director of the Fred T. Korematsu Institute for Civil Rights and Education. She is a former reporter and video producer for TIME in Hong Kong.

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