Who Do You Think You Are?

Who Do You Think You Are? is a series on The BBC where (mostly British) celebrities investigate their family trees. Some celebrities find some very interesting relatives -- including royalty. The series debuted in 2004 and is still ongoing.

The definition of "celebrity" is a little loose and often includes any old BBC presenter with a familiar face and a few weeks to spare, but this is not important as it seems almost anyone has a few fascinating stories in their family tree.

Celebrities on the BBC version have been:

Series One

 * Bill Oddie
 * Amanda Redman
 * Sue Johnston
 * Jeremy Clarkson
 * Ian Hislop
 * Moira Stuart
 * David Baddiel
 * Lesley Garrett
 * Meera Syal
 * Vic Reeves

Series Two

 * Jeremy Paxman
 * Sheila Hancock
 * Stephen Fry
 * Julian Clary
 * Jane Horrocks
 * Gurinder Chadha (director of Bend It Like Beckham)

Series Three

 * Barbara Windsor
 * Robert Lindsay
 * Colin Jackson
 * David Tennant
 * David Dickinson
 * Nigella Lawson
 * Jeremy Irons
 * Julia Sawalha

Adoption Special

 * Nicky Campbell

Series Four

 * Natasha Kaplinsky
 * John Hurt
 * Griff Rhys Jones
 * Carol Vorderman
 * Alistair McGowan
 * Graham Norton
 * Sir Matthew Pinsent

Series Five

 * Patsy Kensit
 * Boris Johnson
 * Jerry Springer
 * Esther Rantzen
 * Ainsley Harriott
 * David Suchet
 * Jodie Kidd
 * Laurence Llewelyn-Bowen

Series Six

 * Rory Bremner
 * Fiona Bruce
 * Rick Stein
 * Zoë Wanamaker
 * Kevin Whately
 * Davina McCall
 * Chris Moyles
 * Kate Humble
 * David Mitchell
 * Kim Cattrall
 * Martin Freeman

Series Seven

 * Bruce Forsyth
 * Rupert Everett
 * Dervla Kirwan
 * Monty Don
 * Rupert Penry-Jones
 * Alexander Armstrong
 * Jason Donovan
 * Hugh Quarshie
 * Alan Cumming

Series Eight

 * J. K. Rowling
 * June Brown
 * Alan Carr
 * Sebastian Coe
 * Larry Lamb
 * Emilia Fox
 * Richard Madeley
 * Len Goodman
 * Tracey Emin
 * Robin Gibb

Other versions of the show have been made for American, Australian, Irish, Canadian and South African television. The American version, produced by Lisa Kudrow, featured Sarah Jessica Parker, Matthew Broderick, Brooke Shields, Emmitt Smith, Susan Sarandon, Spike Lee and Kudrow herself.

Has nothing to do with "Who the hell do you think we are?".

"Harry: If you like The BBC's Who Do You Think You Are, you may be interested in ITV's You Don't Know You're Born, which is the same."
 * Blue Blood: A surprisingly high number of celebrities turn out to have this somewhere in their background. Amongst others chat show host Ryan Tubridy turned out to be descended from Edward III of England.
 * Given the philoprogenitive qualities of Edward and his offspring today it's more a matter of who isn't descended from him!
 * The ultimate example: Sir Matthew Pinsent (knighted for Olympic prowess) turns out to be descended from God. (By extension, so is everyone else who can trace their tree back to Edward the Confessor, but it's Pinsent they show actual proof to.)
 * And comedian Alexander Armstrong manages to trace his family line all the way back to William the Conqueror.
 * Documentary
 * Follow the Leader / Dueling Shows: ITV's "You Don't Know You're Born". As Harry Hill put it:


 * Foreign Remake: In many countries, as noted above.
 * Shown Their Work: Little is dumbed down, and even the maps take historical border changes into account (a common mistake in documentaries).
 * Soundtrack Dissonance: Yes, BBC, the upbeat sounds of "Young Folks" by Peter, Bjorn and John are an excellent choice for most of your trailers for this series. No, BBC, you should not play it over footage of anyone - even Jerry Springer - walking around a former concentration camp, weeping. The effect is most disquieting.
 * Tear Jerker: Almost every celebrity has at least one ancestor who has an incredibly tragic life.
 * And a significant number of them have relatives who witnessed, fled from, or died in the Holocaust.