- On May 21, in a year he doesn't want mentioned, Jeff Seitz was born.
- On 1967-05-21, Andy Summers performed with Zoot Money's Big Roll Band at the Airmen's Club in Bentwaters, England, UK.
- On 1969-05-21, Sting and James Berryman went to St. James Park in Newcastle, England, UK to watch the second game of the UEFA cup semi finals between Newcastle United and Glasgow Rangers.
- On 1973-05-21, Stewart Copeland worked as a tour manager for Joan Armatrading in Darlington, England, UK.
- On 1975-05-21, Curved Air recorded Midnight Wire at Island Studios in London, England, UK.
- On 1976-05-21, Andy Summers performed with Kevin Coyne at the Aula der Universität in Cologne, Germany.
- On 1977-05-21, Stewart Copeland was running some errands in London, England, UK.
- On 1978-05-21, The Police performed at the Kongreßhalle in Böblingen, Germany.
- On 1979-05-21, The Police performed at the Paramount Northwest in Seattle, WA, USA.
- On 1980-05-21, Stewart Copeland recorded the "Star Special" radio show at the BBC in London, England, UK - while Andy Summers was in Ireland.
- On 1981-05-21, Stewart Copeland had a meeting regarding the charity event on 1981-06-01 in London, England, UK.
- On 1982-05-21, a bearded Stewart Copeland filmed the Anti-Nowhere-League concert at the Apollo in Glasgow, Scotland, UK.
- On 1983-05-21, Sting flew from London to Mexico City, Mexico.
- On 1984-05-21, the URGH! A Music War VHS was released in Japan.
- On 1985-05-21, Sting rehearsed with his band at the Château de Courson in Paris, France.
- On 1987-05-21, Sting recorded ...Nothing Like The Sun at AIR Studios on Montserrat.
- On 1988-05-21, ...Nada Como El Sol was released in Japan.
- On 1989-05-21, Animal Logic rehearsed for their European tour in London, England, UK.
- On 1990-05-21, Sting was recording The Soul Cages at Studio Guillaume Tell in Paris, France.
- On 1991-05-21, Andy Summers started recording World Gone Strange in New York, NY, USA - while Sting talked at a press conference in Milan, Italy.
- On 1993-05-21, Sting and his band flew from Denver to Dallas, TX, USA.
- On 1994-05-21, Andy Summers performed at Oxford Playhouse in Oxford, England, UK (in the afternoon) and at the Bloomsbury Theatre in London, England, UK (in the evening).
- On 1998-05-21, Andy Summers performed at the Teatro do SESC in Ribeirao Preto, Brazil.
- On 2000-05-21, Andy Summers participated in an online chat presented by Guitar.com - while Sting spent a day off in Verona, Italy.
- On 2007-05-21, The Police rehearsed at the Chief Joe Mathias Centre in Vancouver, BC, Canada.
- On 2008-05-21, The Police performed at Superpages.com Center in Dallas, TX, USA.
- On 2009-05-21, Sting performed at the One Night Live benefit concert at the Air Canada Centre in Toronto, Canada.
- On 2010-05-21, Henry Padovani was in Cannes, France - while Sting was flying to Dallas, TX, USA.
- On 2013-05-21, Sting watched an ice hockey game (New York Ranger vs Boston Bruins) at Madison Square Garden in New York, NY, USA.
- On 2014-05-21, Sting and Trudie Styler attended The Posse Foundation's 25th Anniversary Gala Celebration at Cipriani Wall Street in New York, NY, USA - while Stewart Copeland was interviewed in London, England, UK.
- On 2015-05-21, Andy Summers was taking photos in Shanghai, China.