List of Famous people born on June 21st

Christian Detlev, Count von Reventlow (1671–1738) was a Danish military leader and diplomat.

Sergey Aleksandrovich Sergeev (June 21, 1964 – 1989), known as the "Zaporizhzhia Maniac", was a Soviet spree killer who killed four people in Zaporizhzhia and Yalta in 1987–1988.

Paolo Soleri was an Italian architect. He established the educational Cosanti Foundation and Arcosanti. Soleri was a lecturer in the College of Architecture at Arizona State University and a National Design Award recipient in 2006. He coined the concept of 'arcology' – a synthesis of architecture and ecology as the philosophy of democratic society. He died at home of natural causes on 9 April 2013 at the age of 93.

Kenneth Joseph Matthews, MBE was a British race walker, who won the Olympic (1964) and European (1962) titles in the 20 km walk.

Margaret Mary Heckler was an American Republican Party politician who represented Massachusetts in the United States House of Representatives from 1967 to 1983 and served as Secretary of Health and Human Services and Ambassador to Ireland under President Ronald Reagan.

Major Charles Murray Kennedy St Clair, 17th Lord Sinclair, CVO, DL was a Scottish peer who spent his entire life in the service of the Crown; as a soldier, an officer of arms, an equerry in the Queen Mother's Household, a representative peer and as a Lord Lieutenant.

Sir John Helias Finnie McEwen, 1st Baronet or Jock McEwen, was a Scottish Unionist politician who served in the House of Commons as Conservative Member of Parliament for Berwick and Haddington from 1931 until 1945.

Eldar Memišević is a Bosnian-born Qatari handball player for El Jaish and the Qatari national team.