William Mapother Biography

William Mapother is an American actor and entrepreneur who became famous after appearing as Ethan Rom in the hit series ‘Lost’. Check out this biography to know about his childhood, family life, achievements and fun facts about him.

Quick Facts

Birthday: April 17, 1965

Nationality: American

Famous: Actors American Men

Age: 54 Years, 54 Year Old Males

Sun Sign: Aries

Also Known As: William Reibert Mapother Jr.

Born in: Louisville, Kentucky

Famous as: Actor

Height: 6'1" (185 cm), 6'1" Males


father: William Reibert Mapother Sr.

mother: Louisa Riehm Mapother

U.S. State: Kentucky

City: Louisville, Kentucky

More Facts

education: University of Notre Dame

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William Reibert Mapother Jr. is an American actor and entrepreneur who rose to fame after appearing as Ethan Rom in the hit series ‘Lost’. Prior to embarking on an acting career, Mapother worked as a school teacher in Los Angeles for three years. Despite not being actively involved in films, he knew enough about them thanks to his cousin Tom Cruise. He made his professional debut in the 1989 movie ‘Born on the Fourth of July’ and subsequently began appearing in other Cruise-starring films in minor roles. He worked in the movies, such as ‘Magnolia’, ‘Mission Impossible: 2’, and ‘Minority Report’. Later, he branched out on his own and started making guest appearances in popular TV series. He received his breakthrough when he was cast in a recurring role on the supernatural show ‘Lost’. The role of Ethan on ‘Lost’ can be considered to be the highlight of his career. After tasting success and fame in Hollywood, Mapother decided to take on more independent projects and starred in critically acclaimed films like ‘In the Bedroom’ and ‘Another Earth’. His recent works include the films ‘The Atticus Institute’ and ‘Tell Me How I Die’. Apart from acting, he is a co-founder of the finance company ‘Slated’.

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  • William Mapother’s cousin is the reigning Hollywood superstar, Tom Cruise, and it was in one of his most critically-acclaimed early films ‘Born on The Fourth of July’ (1989) that Mapother made his acting debut. However, it was not until almost a decade later that he was able to establish himself as a known actor. Before following his cousin into the world of entertainment, Mapother studied English literature at the University of Notre Dame and worked as a school teacher for three years. He taught middle-school students in various schools of Los Angeles. However, the acting bug bit him soon, and he started studying dramatics at the D.W. Brown Acting School in Santa Monica, California.
  • It was in the Billy Crudup-starrer film ‘Without Limits’ (1998) that Mapother was first noticed, and not long after that, a string of movie roles came his way. He worked alongside his cousin Tom Cruise in films, such as ‘Magnolia’ (1999), ‘Mission impossible: 2’ (2000) and the much-acclaimed science-fiction thriller ‘Minority Report’ (2002), directed by ace filmmaker Steven Spielberg. Meanwhile, Mapother was also working in television shows, making guest appearances in long-running crime procedurals like ‘CSI: Crime Scene Investigation’ (2002), ‘Law and Order: Special Victims Unit’ (2003) and ‘NCIS’ (2004). However, in 2004, he landed the role that he is now most widely recognized for: Ethan Rom in the supernatural drama ‘Lost’ (2004-2010). Over the course of six years, Mapother appeared in only 11 episodes of the seminal show. Despite not being a series regular, he became one of the most recognized and popular characters of the show, earning a loyal fanbase. His character Ethan dies in the first season but later reappears in flashback scenes and through time travel.
  • Post his role on ‘Lost’, Mapother has gone on to star in a series of highly successful TV shows, including ‘Castle’ and ‘The Mentalist’. His TV portfolio seems to be populated by crime dramas, including ‘Criminal Minds’, ‘Prison Break’ and ‘Justified’. He also appeared in recurring roles on series like ‘Ro’, ‘The Lottery’, ‘Minority Report’, ‘Powers’, ‘Supergirl’, and ‘MacGyver’. Besides appearing in movies, and several TV shows, Mapother has also lent his voice to video games, including the immensely successful ‘Hitman’ (2016) and ‘Fallout: New Vegas’ (2010). The character actor has also starred in several independent and big budget films, such as ‘Another Earth’ (2011), ‘Citizen Gangster’ (2011), ‘Static’ (2012), ‘Underdogs’ (2013), ‘It’s Dark Here’ (2013), ‘I Origins’ (2014), ‘Blackhat’ (2015), and ‘The Atticus Institute’ (2015). More recently, he was seen in guest roles on TV series ‘The Blacklist’ (2018) and ‘Lethal Weapon’ (2018). His upcoming film ‘Son of Monarchs’, a drama directed by Alexis Gambis, will have him in a lead role. The movie is scheduled for release in 2019.
  • Mapother was selected among the National Board of Directors for the Screen Actors Guild in 2007, and remained part of the association for three years. He is also a co-founder of the Flyover Film Festival, through which he aims to support up and coming actors. He is a member of Kentucky Film Commission. Apart from films, Mapother is also an entrepreneur who is a founding partner of the tech and finance company ‘Slated’. He is an active philanthropist as well, often speaking about the issues related to elder abuse.
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Family & Personal Life
  • William Mapother was born on April 17, 1965 in Louisville, Kentucky to Louisa and William Reibert Mapother Sr. His father was a reputed attorney, bankruptcy consultant, and judge. The family traces its roots to England, Ireland, and Germany. He has two sisters: Amy Mapother and Katherine Mapother. He is related to Tom Cruise, who is his first cousin, from his father’s side. Mapother graduated from Xavier High School in Kentucky, and later studied English at the University of Notre Dame. He has not revealed any information about his personal life or current relationship status.
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Article Title
- William Mapother Biography
- Editors, TheFamousPeople.com
- TheFamousPeople.com
Last Updated
- March 19, 2019
William Mapother

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