1. On December 13, 1868, the Fort Shaw Indian School was established in Montana. The school was part of the US government's efforts to assimilate Native American children into white culture.

2. In 1890, Montana became the 41st state in the Union on December 13.

3. On December 13, 1943, a B-17 bomber crashed near Helena, Montana, killing all 10 crew members on board. The crash was caused by severe weather conditions during a training flight.

4. In 1993, a Montana man named Ted Kaczynski was arrested for the Unabomber bombings that had terrorized the nation for almost 20 years. Kaczynski pled guilty to the bombings on December 13, 1995.

5. On December 13, 2010, the Montana State Capitol was evacuated after a bomb threat was received. The building was searched and no explosives were found, but the threat caused a significant disruption in the state's government operations.