Ioan Gruffudd was born on 6 October 1973; his birth was registered in Aberdare in the South Wales valleys, though he was raised mainly in Cardiff from around the age of eight. He grew up speaking Welsh, was a talented oboist as a teenager, and began acting at just thirteen with a regular role in the long-running Welsh-language soap opera Pobol y Cwm.
After training at the Royal Academy of Dramatic Art in London, Gruffudd took the title role in a 1996 television adaptation of Poldark. He built on that early success with film roles including Oscar Wilde's lover John Gray in Wilde (1997) and Fifth Officer Harold Lowe in James Cameron's Titanic (1997), before becoming widely known as the lead of the ITV/A&E Hornblower series of television films between 1998 and 2003.
His film career broadened through the 2000s, with parts in 102 Dalmatians (2000), Black Hawk Down (2001) and King Arthur (2004), and international stardom followed when he was cast as Reed Richards, also known as Mr Fantastic, in Fantastic Four (2005) and its sequel Fantastic Four: Rise of the Silver Surfer (2007). He also played the British abolitionist William Wilberforce in Amazing Grace (2006).
Gruffudd has gone on to build a substantial American television career, with regular roles in series including Ringer, Forever and Harrow. He remains one of Wales's best-known actors on the world stage and has spoken often about his Welsh-speaking upbringing in Cardiff.