What happened on May 21

75 documented historical events happened on May 21, from antiquity to the present day. The best known is this: Arab–Byzantine wars: The city of Syracuse was captured by the Aghlabids (pictured) as part of the Muslim conquest of Sicily. On the same day, in another year: The Crusades: The siege of Shaizar ended, and the Emir of Shaizar became a vassal of the Byzantine Empire. On Almanaccolo every event is listed in chronological order, grouped by century, and links to the Wikipedia article it comes from, so you can always read further or check the source. Alongside the events you find who was born and who died on this date, and which observances are celebrated around the world.

160 people with a Wikipedia article were born on May 21, including Jocasta Innes, Günter Blobel, Heinz Holliger. The list spans every era and every field — art, science, politics, sport, entertainment — ordered by year of birth, from the earliest to the most recent. The six featured people are those most has been written about: the ordering uses the length of their Wikipedia article as an indicator of prominence. For each one you find their occupation, year of birth and a link to the full biography.

116 people with a Wikipedia article died on May 21, including Sun Quan, Feng Dao, Louis V of France. The list is in chronological order by year of death and spans all of documented history, from antiquity to the present day. For each person you find their occupation, the year and a link to the Wikipedia biography, where the full story and its sources can be read.

17 observances are celebrated on May 21 around the world: Afro-Colombian Day (Colombia), Christian feast day: Blessed Adílio Daronch and Manuel Gómez González, Christian feast day: Blessed Franz Jägerstätter, Christian feast day: Earliest day on which Corpus Christi can fall, while June 24 is the latest; held on Thursday after Trinity Sunday (often locally moved to Sunday). (Roman Catholic Church), Christian feast day: Eugène de Mazenod, Christian feast day: Helena of Constantinople, also known as "Feast of the Holy Great Sovereigns Constantine and Helen, Equal-to-the-Apostles." (Eastern Orthodox Church, Anglican Communion). The list gathers national holidays, international days and religious or civil observances falling on this date in different countries, as recorded on Wikipedia. Some are fixed and recur on the same day every year; others depend on the local calendar. Each links to the article explaining its origin and meaning.