Okonedo was born in the East End of London to a British Nigerian father and a Jewish mother. She was brought up in relative poverty by her mother, and later attended the Royal Academy of Dramatic Art. She has one daughter from a previous relationship with Irish film editor Eoin Martin.
Okonedo was nominated for the Academy Award for Best Supporting Actress for her role as Tatiana Rusesabagina in Hotel Rwanda (2004). She later received a Golden Globe Award nomination for the miniseries Tsunami: The Aftermath (2006) and BAFTA TV Award nominations for the drama series Criminal Justice (2009) and the television film Mrs. Mandela (2010). Her television credits include Queen Margaret of Anjou in BBC's The Hollow Crown.
In 2010, she was appointed an Officer of the Order of the British Empire (OBE), and in 2019 was appointed a Commander of the Order of the British Empire (CBE) by Queen Elizabeth II.
Okonedo's casting as Siuan Sanche was announced on August 19, 2020.
- at the Internet Movie Database