After a four-year hiatus, the popular series Who Do You Think You Are? returns to television, and fans are looking back on all of the celebrities who have shared their journeys on the show. Who Do You Think You Are? features celebrities who want to research their genealogy. As they trace their family trees, they learn more about themselves and their ancestors' historical experiences. They travel to locations in the United States and all over the world, as they piece together the stories of those who came before them, with the help of historians, genealogists, and other experts.

The American version of Who Do You Think You Are? is an adaptation of the British series of the same name, which airs on the BBC. It premiered in 2010 on NBC, and ran for three seasons, until it moved to TLC for seven seasons. It will return to NBC this summer for season 11, with Lisa Kudrow and Dan Bucatinsky as executive producers.

Related: Why Who Do You Think You Are? Is Such An Important Show

The Emmy-nominated series Who Do You Think You Are? delivers emotional and powerful episodes that not only give insight into the lives of celebrities, but also teach people about history. By shining a light on the personal side of the past, Who Do You Think You Are? opens viewers' hearts and minds to the experiences of different people. Ahead of the show's season 11 premiere, here is information about every celebrity who has ever appeared on Who Do You Think You Are?.

Season 1 (2010)

Susan Sarandon Who Do You Think You Are

Who Do You Think You Are? season 1 premiered on March 5, 2010 on NBC. The first episode featured actress Sarah Jessica Parker. That show was followed by episodes featuring retired NFL star Emmitt Smith, actress Lisa Kudrow, actor Matthew Broderick, actress Brooke Shields, actress Susan Sarandon, and director Spike Lee.

Season 2 (2011)

Rosie O'Donnell Who Do You Think You Are

During Who Do You Think You Are? season 2, viewers first followed singer and actress Vanessa L. Williams' journey. The show then aired episodes starring country music singer Tim McGraw, television personality Rosie O'Donnell, singer Lionel Richie, actor Steve Buscemi, actress Gwyneth Paltrow, and actress Ashley Judd. In addition, an edited version of Kim Cattrall's 2009 episode from the British series was included in this season.

Season 3 (2012)

Blair Underwood Who Do You Think You Are

Who Do You Think You Are? season 3 began with actor Martin Sheen, and continued with actress Marisa Tomei, actor Blair Underwood, country music singer Reba McEntire, retired NFL star Jerome Bettis, and actress Helen Hunt. In addition, the second half of the season featured actress Rita Wilson, actress Edie Falco, actor Rob Lowe, actress Rashida Jones, actor Jason Sudeikis, and celebrity chef Paula Deen.

Season 4 (2013)

Kelly Clarkson Who Do You Think You Are.jpg

After Who Do You Think You Are? was cancelled by NBC, TLC began airing the series for season 4. The first episode featured singer Kelly Clarkson, and was followed by episodes that starred actress Christina Applegate, comedian Chelsea Handler, actress and singer Zooey Deschanel, actor Chris O'Donnell, model Cindy Crawford, country music singer Trisha Yearwood, and actor Jim Parsons.

Season 5 (2014-15)

Valerie Bertinelli Who Do You Think You Are

Who Do You Think You Are? season 5 began with actress Cynthia Nixon's journey. It then aired episodes that featured actor Jesse Tyler Ferguson, actress Valerie Bertinelli, actor Kelsey Grammer, television host Julie Chen, singer Josh Groban, actress Angie Harmon, actor Sean Hayes, actor Tony Goldwyn, actress America Ferrera, actor Bill Paxton, and singer Melissa Etheridge. The season also aired an episode that starred actress Rachel McAdams and her sister Kayleen McAdams, who is a Hollywood make-up artist. In addition, the network aired an edited version of Minnie Driver's 2013 BBC episode.

Season 6 (2015)

Bryan Cranston Who Do You Think You Are

For Who Do You Think You Are? season 6, TLC aired an edited version of author J.K. Rowling's 2011 BBC episode. The season also starred actress Ginnifer Goodwin, actress Alfre Woodard, actor Bryan Cranston, and television host Tom Bergeron. In addition, this season featured an "Into the Archives" episode that revisited some of the most emotional and shocking discoveries from past seasons of Who Do You Think You Are?

Season 7 (2016)

Aisha Tyler Who Do You Think You Are

Who Do You Think You Are? season 7 began with actress Aisha Tyler's episode. It continued with actor Scott Foley, actress Katey Sagal, actress Molly Ringwald, actor Chris Noth, and actress Lea Michele.

Season 8 (2017)

John Stamos Who Do You Think You Are

Who Do You Think You Are? season 8 kicked off with an episode about actress Courteney Cox. It also included the adventures of actress Julie Bowen, actress Jennifer Grey, actor Noah Wyle, actress Jessica Biel, singer Smokey Robinson, actor John Stamos, and actress Liv Tyler.

Season 9 (2018)

Laverne Cox Who Do You Think You Are

Actor Jon Cryer's episode was the first from Who Do You Think You Are? season 9. It then aired the experiences of actresses Laverne Cox, Megan Mullally, Molly Shannon, Jean Smart, and actress and singer Hilary Duff.

Season 10 (2018)

Mandy Moore Who Do You Think You Are

Later in 2018, Who Do You Think You Are? season 10 premiered with four episodes. They featured actress and singer Mandy Moore, actor Josh Duhamel, actress Regina King, and actor Matthew Morrison.

Season 11 (2022)

Billy Porter Who Do You Think You Are

Who Do You Think You Are? returns to NBC in July. The upcoming season will follow the journeys of actress Allison Janney, and actors Zachary Levi, Nick Offerman, Billy Porter, Zachary Quinto, and Bradley Whitford.

Who Do You Think You Are? has taught viewers so much through the extensive research of these celebrities' family trees and genealogy. They have made discoveries that range from joyous to tragic, but all of them have been inspiring. The show encourages viewers to look in their own mirrors and ask themselves, Who Do You Think You Are?.

Next: Who Do You Think You Are? Season 11 Promo Reveals Emotional Journeys

Who Do You Think You Are? season 11 premieres on Sunday, July 10 on NBC.