1. On March 18, 1889, the Minnesota State Capitol building was dedicated. It is one of the largest and tallest capitol buildings in the United States, standing 223 feet tall.

2. In 1965, on March 18th, Minnesota became the first state to implement the Community Action Program, part of President Lyndon B. Johnson's War on Poverty. The program aimed to provide comprehensive services to low-income families and communities.

3. March 18, 1922, marked the opening of the Foshay Tower in Minneapolis. The tower, named after its owner Wilbur Foshay, was the tallest building in Minneapolis until the IDS Tower was built in 1973.

4. On March 18, 1998, one of the deadliest tornado outbreaks in Minnesota's history struck the state. The tornadoes killed two people and caused millions of dollars in damages.

5. In 1857, on March 18th, the Treaty of Washington was signed between the United States and the Sioux Tribe. The treaty ceded a portion of land in Minnesota to the United States, which later became part of the state. However, the Sioux later contested the treaty, leading to the US-Dakota War of 1862.