1. On December 18, 1902, Idaho's first governor, George Laird Shoup, passed away in Boise. Shoup played a significant role in the state's early history, helping to draft Idaho's constitution and serving as governor from 1890 to 1893.

2. The first ski lift in the western United States was installed at Sun Valley Resort in Idaho on December 18, 1936. The resort, which was developed by the Union Pacific Railroad, became a popular destination for celebrities and skiers alike.

3. On December 18, 1944, the Teton Dam was authorized by the U.S. Bureau of Reclamation. The dam, located in eastern Idaho, was designed to provide irrigation water for farmland and generate hydroelectric power. However, the dam's failure in 1976 resulted in a massive flood that caused extensive damage and loss of life.

4. The Idaho State Capitol Building was officially dedicated on December 18, 1920. The building's construction had begun in 1905 but had been delayed due to funding issues and the outbreak of World War I.

5. On December 18, 1805, the Lewis and Clark Expedition arrived at Weippe Prairie in northern Idaho, an area lived in by the Nez Perce tribe. The Nez Perce provided the expedition with food and shelter, and the meeting helped to establish a peaceful relationship between the two groups.