Wikipedia:Selected anniversaries/January 18
- 1778 - Captain James Cook discovered the Sandwich Islands, now known as Hawaii.
- 1871 - King Wilhelm I of Prussia was proclaimed the first Kaiser of the German Empire, a newly unified nation state.
- 1958 - Willie O'Ree of the Boston Bruins played his first game in the National Hockey League, breaking the color barrier in professional ice hockey.
- 1977 - The mysterious Legionnaires' disease was found to be caused by a novel bacterium now known as Legionella.
- 2003 - The Canberra Firestorm: Bushfires burning out of control began blazing through residential areas of Canberra, Australia.
Recent days: January 17 – January 16 – January 15