1. January 18, 1872: The Black Hills Expedition departed Fort Laramie, Wyoming, headed for the Black Hills of South Dakota. The expedition was led by Lt. Colonel George Armstrong Custer and included over 1,000 soldiers, as well as miners and prospectors. Custer's expedition would ultimately lead to the discovery of gold in the Black Hills and the subsequent gold rush.

2. January 18, 1887: The Dawes Act was passed, which authorized the President of the United States to survey Native American tribal land and divide it into individual allotments for Native Americans. This act was meant to assimilate Native Americans into American society and encourage private ownership of land. However, the Dawes Act had devastating consequences for many Native American communities and caused the loss of millions of acres of tribal land.

3. January 18, 1919: South Dakota became the first state in the United States to ratify the 19th Amendment to the Constitution, which granted women the right to vote. South Dakota's support for women's suffrage was influenced by the state's strong tradition of women's suffrage activism.

4. January 18, 1964: The Pine Ridge Indian Reservation in South Dakota was the site of the Wounded Knee Incident, a political protest by members of the Oglala Lakota tribe. The protest was the first major armed confrontation between Native Americans and the U.S. government since the late 19th century. The incident lasted for 71 days and resulted in two deaths and numerous injuries.

5. January 18, 2002: The Crazy Horse Memorial Foundation and the South Dakota Department of Transportation reached an agreement to redesign the nearby section of U.S. Highway 16/385 to include a $1.8 million interpretive center dedicated to the life and legacy of Crazy Horse. The Crazy Horse Memorial is a massive and ongoing mountain carving project located in the Black Hills. Once completed, it will be the largest memorial to any Native American figure in history.