1. Iowa's First Librarian Was Appointed on March 15, 1838
On March 15, 1838, the Iowa Territorial Library was established, and its first librarian was appointed. John Frost, a lawyer from Pennsylvania, was selected as the library's first librarian. The Iowa Territorial Library was opened to the public later that year, and it contained around 600 books and was located in a small room at the Territorial Capitol.

2. Iowa Became a State on March 15, 1846
On March 15, 1846, Iowa officially became the 29th state in the United States of America. Iowa was the first state to be admitted to the Union after the original 13 colonies and was the only state admitted during President James K. Polk’s administration.

3. The Iowa State Capitol Dome Was Completed on March 15, 1884
On March 15, 1884, the Iowa State Capitol's iconic dome was completed. The dome, which stands 275 feet tall, is made of steel and covered with 23-karat gold leaf. The dome is a symbol of Iowa's government and has been featured on the state's license plates and in many other official capacities.

4. The Iowa State Senate Passed a Bill Allowing Sunday Liquor Sales on March 15, 2010
On March 15, 2010, the Iowa State Senate passed a bill allowing Sunday liquor sales in the state. The bill was controversial, with some lawmakers arguing that it would increase alcohol-related problems in the state. However, supporters of the bill argued that it would help businesses and generate more revenue for the state.

5. The Iowa State Cyclones Won Their First NCAA Basketball Tournament Game on March 15, 2012
On March 15, 2012, the Iowa State Cyclones men's basketball team won their first NCAA Tournament game in over a decade. The Cyclones defeated the University of Connecticut Huskies with a score of 77-64 in the second round of the tournament. The team was led by Royce White, who had 13 points and 10 rebounds.