21 June is the 172nd day of the year (173rd in leap years). There are 193 days remaining until the end of the year.
- 1884: A riot takes place at the Ministry of Magic, in Whitehall, over the ministerial decision to introduce the Stooging Penalty to Quidditch. The assembled demonstrators bombard the representative from the Department of Magical Games and Sports with Quaffles, and threaten to stooge the Minister for Magic, Faris Spavin.
- In the tale The Fountain of Fair Fortune by Beedle the Bard, this was the day when a chosen one could gain access to the Fountain of Fair Fortune.