Glenda May Jackson CBE (9 May 1936, Birkenhead, Cheshire – 15 June 2023) was an English actress and politician. She was one of the few artists to achieve the Triple Crown of Acting, having won two Academy Awards, three Emmy Awards and a Tony Award. She was made a CBE by Queen Elizabeth II in 1978.

She won the Academy Award for Best Actress twice: for her roles in Women in Love (1970) and A Touch of Class (1973). She won the BAFTA Award for Best Actress in a Leading Role for Sunday Bloody Sunday (1971). Her other notable roles include Mary, Queen of Scots (1971), Hedda (1975), The Incredible Sarah (1976) and Hopscotch (1980). She won two Primetime Emmy Awards for her role as Elizabeth I in the BBC series Elizabeth R (1971). She received the British Academy Television Award for Best Actress for her role in Elizabeth Is Missing (2019).

Jackson studied at the Royal Academy of Dramatic Art (RADA). She made her Broadway debut in Marat/Sade (1966). She received five Laurence Olivier Award nominations for her West End roles in Stevie (1977), Antony and Cleopatra (1979), Rose (1980), Strange Interlude (1984) and King Lear (2016), the later being her first role after a 25 year absence from acting, which she reprised on Broadway in 2019. She won the Tony Award for Best Actress in a Play for her role in the revival of Edward Albee's Three Tall Women (2018).

Jackson took a hiatus from acting to take on a career in politics from 1992 to 2015, and was elected as the Labour Party MP for Hampstead and Highgate in the 1992 general election. She served as a junior transport minister from 1997 to 1999 during the government of Tony Blair, later becoming critical of Blair. After constituency boundary changes, she represented Hampstead and Kilburn from 2010. At the 2010 general election, her majority of 42 votes, confirmed after a recount, was the narrowest of that parliament. Jackson stood down at the 2015 general election and returned to acting.