George Andrew J. Mackay was born on March 13, 1992 in Hammersmith, London. He was raised by his parents, Kim Baker, a costume designer and father Paul MacKay, an Australian of Scots-Irish descent, from Adelaide, who works in lighting/stage management. His parents enrolled him in the Independent Harrodian School which encouraged his love of drama.
In 2002, at the age of ten, MacKay was discovered at The Harrodian School by an acting scout who approached him asking if he was interested in auditioning for a role in Peter Pan. MacKay attended a workshop and won the role of one of the Lost Boys, Curly, in what was the start of his career. At the age of 13, he played the role of Riccio in The Thief Lord, which became Cornelia Funke’s best-selling children’s novel.
MacKay has appeared in many films such as, The Boys Are Back, Private Peaceful, How I Live Now, Sunshine on Leith, For Those in Peril, Pride, Captain Fantastic, Where Hands Touch, Ophelia, and 1917 which was the latest movie he starred in.