1. On December 16, 1790, the first session of the U.S. Congress was held in Philadelphia, which was then the capital of the country.

2. In 1862, the Battle of Fredericksburg was fought in Virginia, just a few hours south of Washington D.C. The Union Army suffered a crushing defeat against the Confederate Army led by General Robert E. Lee.

3. On December 16, 1916, the National Park Service was created as a bureau within the Department of the Interior. This agency is responsible for preserving and maintaining national parks and monuments in the United States.

4. In 1944, the landmark Supreme Court case of Korematsu v. United States was argued in front of the court. The case dealt with the constitutionality of President Franklin D. Roosevelt's Executive Order 9066, which authorized the internment of Japanese Americans during World War II.

5. On December 16, 1991, the United States and eleven other countries signed the Alma-Ata Protocol in Kazakhstan, officially dissolving the Soviet Union and creating the Commonwealth of Independent States. This event marked the end of the Cold War and the beginning of a new era in international relations.