1. On January 20, 1936, Oklahoma union leader Tom Haggerty was assassinated. Haggerty had been leading a strike of oil field workers in Seminole County, which had turned violent when the oil companies hired armed guards to break up the strike. Haggerty was shot by an unknown gunman while driving home from a meeting with Governor Ernest W. Marland.

2. In 1893, Oklahoma Territory Governor William C. Renfrow was inaugurated on January 20. Renfrow had been appointed by President Benjamin Harrison to replace the previous governor, who had been removed from office due to allegations of corruption. Renfrow's administration was focused on improving the infrastructure of the territory, including building new schools, roads, and bridges.

3. January 20, 2001, was the day of the Oklahoma City Thunder's inaugural game. The team, originally known as the Seattle SuperSonics, had been relocated to Oklahoma City due to a lack of fan support in Seattle. The Thunder played their first game at the Ford Center (now Chesapeake Energy Arena) against the Milwaukee Bucks, but lost 98-87.

4. On January 20, 1961, John F. Kennedy was inaugurated as the 35th President of the United States. Oklahoma Senator Robert S. Kerr was one of Kennedy's strongest supporters in the Senate, and played a key role in passing many of Kennedy's legislative agendas, including the Water Pollution Control Act and the Area Redevelopment Act.

5. In 1977, Oklahoma Governor David Hall was inaugurated on January 20 for his second term in office. Hall had been the first governor in the state's history to be elected to a second consecutive term, but his administration was plagued by scandal and controversy. He was later convicted of extortion, conspiracy, and perjury, and served time in federal prison.