Portal:Australia/Anniversaries/January/January 21
- 1887 – Brisbane receives a daily rainfall of 465 millimetres (18.3 inches), a record for any Australian capital city.
- 1904 – Henry Northcote, 1st Baron Northcote is appointed the third Governor General of Australia.
- 1918 – The Mackay cyclone struck Mackay, Queensland, causing serious damage and killing 30.
- 1931 – Isaac Isaacs becomes the first Australian born Governor-General of Australia
- 1941 – World War II: Australian and British forces attack Tobruk, Libya.
- 1966 – Richard Layton Butler, Premier of South Australia, dies.
- 1974 – Entertainer, Rove McManus is born.