PIERRE, S.D. -- South Dakotans, who said goodbye to Columbus Day 16 years ago and renamed it Pioneer Day to honor state settlers, celebrated yesterday under yet another name, Native Americans Day, and under somewhat ironic circumstances.

Until earlier this year, the state was still refusing to designate Martin Luther King Jr. Day an official holiday. But officials said the new celebration of Native American heritage marks a shift in state government attitudes toward non-white residents.

The unlikely catalyst in helping to change minds in the legislature was a young cowboy named Lynn Hart. Describing himself as half-Sioux and half-black, Hart, 29, told the predominantly white, middle-aged lawmakers last January that his friends on the rodeo circuit viewed South Dakota as racist for refusing to honor King.

A few days later, in a sudden turnabout, Republican leaders declared support for King Day as an official holiday each January. In a bit of partisan one-upsmanship, because Democrats had led the long fight to establish King Day, the Republicans also called for renaming Pioneer Day as Native Americans Day.

"It marked the end of public tolerance for open expression of bigotry and beginning of an appreciation of a struggle most of us can't understand," said state Sen. Scott Heidepriem (R). "It . . . just took a little longer for what was considered conservative to become embarrassing and bigoted."

Although the 1973 gun battles at Wounded Knee between federal agents and Sioux Indians brought the state notoriety, relations have appeared relatively peaceful for a decade between the 45,000 Indians and 640,000 non-Indians in this vast, poor and thinly populated state. Several counties, including the Pine Ridge and Rosebud Sioux reservations, are among the nation's most impoverished.

Last month, Mike Whalen of Lake Andes, a deputy prosecutor in Charles Mix County, stunned white and Indian communities by speaking as a private citizen in opposition to a zoning change for a Native American women's shelter. He described Indian culture as one of "hopelessness, Godlessness, of joblessness and lawlessness."

Whalen's statements were "a shot heard around the state -- around the country, actually," said Charon Asetoyer, executive director of the Native American Women's Health Education Resource Center, which planned the shelter.

Shirley Bordeaux, a Native American who lives in Sioux Falls, the state's largest community, said she nearly cried when she saw newspaper accounts. "I find it totally unacceptable and frightening," said Bordeaux, a member of the governor's Council for the Year of Reconciliation, created in January to promote better relations between Indians and non-Indians. The council called for Whalen's resignation and issued a public apology.

Tim Giago, publisher of the Lakota Times, an Indian newspaper based in Rapid City, challenged Gov. George S. Mickelson (R) last December to declare a statewide year of reconciliation as an appropriate acknowledgment of the 100th anniversary of the Wounded Knee massacre and the killing of Sitting Bull.

Mickelson accepted, appointing the council and engaging in a peace-pipe ceremony in the Capitol rotunda with leaders of the nine Sioux nations with land inside the state. More recently, he has called for "a century of reconciliation" and suggested a permanent council comprising equal numbers of Indians and non-Indians to plan and promote better understanding.

The primary celebration of Native Americans Day occurred at Crazy Horse Mountain near Mount Rushmore National Monument in the Black Hills. At the site is a giant stone carving of the 19th-century Sioux warrior who helped to defeat Col. George A. Custer at the Little Bighorn June 25, 1876, a date quietly marked as an unofficial holiday by some Sioux tribal governments.

Some whites have called the Year of Reconciliation unnecessary. Some Sioux leaders describe it as a necessary beginning, while others see it as superficial.

Mickelson said he is taking a pragmatic approach to relations between the state and the Sioux. "I'm in the here and now," he said. "You can't change what's happened in the past. There are a lot of things we can change in the future."