A timeline of their love story...
May 2004: Although Brad is married to Jennifer Aniston at the time, rumours of an on-set romance swirl after Pitt and Angelina Jolie start filming Mr & Mrs Smith.
January 2005: Brad and Jennifer announce in a joint statement that after 'much thoughtful consideration' they had decided to split. They add: 'We happily remain committed and caring friends with great love and admiration for one another.'
March 2005: Jennifer files for divorce citing 'irreconcilable differences' as speculation about Brad and Angelina's romance continued.
April 2005: Brad and Angelina's relationship is confirmed after paparazzi photographs of them on holiday in Kenya with her son Maddox surfaced. They have yet to speak publicly about it.
July 2005: Jennifer is reportedly left heartbroken when Brad and Angelina take part in a revealing photoshoot for W magazine entitled Domestic Bliss. The photo essay shows them as a couple with children. Later that month Angelina adopts her second child, daughter Zahara, from Ethiopia.
September 2005: Jennifer slams Brad as having a 'sensitivity chip missing' following the W photo shoot, which he brainstormed.
October 2005: Brad and Aniston's divorce is finalized.
January 2006: Angelina and Brad announce she is pregnant with their first child while Brad applies to formally adopt her children Maddox and Zahara.
May 2006: The couple's first biological child Shiloh Nouvel Jolie-Pitt born in Swakopmund, Namibia.
December 2006: Angelina tells Vogue that while filming Mr & Mrs Smith, she couldn't 'wait to get to work' to see Brad. Two years later, Jennifer brands the comments 'uncool.'
March 2007: Jolie adopts three-year-old Pax Thien from Vietnam.
May 2008: At the Cannes Film Festival, Angelina confirms she is expecting twins. Knox Leon and Vivienne Marcheline are born in July.
October 2008: Angelina reveals her romance with Brad began while he was married to Jennifer as she says they 'fell in love' on the set of Mr & Mrs Smith. The pair had always maintained up until this point that their relationship only started after he split from Jennifer.
September 2011: Brad tells Parade magazine that before Angelina he 'wasn't living an interesting life.' He added: 'I think that my marriage had something to do with it. Trying to pretend the marriage was something that it wasn't.' He said he's finally a 'satisfied man' with Angelina. He later insistevd the comments were misunderstood, adding: 'Jen is an incredibly giving, loving, and hilarious woman who remains my friend.'