William Stanley Baker was born on 28 February 1928 at 32 Albany Street, Ferndale, in the Rhondda Fach valley of Glamorganshire the youngest of three children of John Henry Baker, a haulier and engineman, and his wife Elizabeth Louisa. He grew up what he called a self-declared wild child, ducking school whenever he could, fighting, playing football. His father lost a leg in a pit accident underground, and the young Stanley resolved early that the mines; his idea of hell, would never claim him. He saw two ways out: boxing or acting. When a teacher at Ferndale Secondary School named Glynne Morse recognised something in the angry, intense, self-willed boy with a fine speaking voice, a smouldering inner life he steered him firmly towards the stage.
At fourteen, while performing in a school play, Baker was spotted by a talent scout from Ealing Studios and cast in Undercover (1943), a wartime film about Yugoslav guerrillas. He was paid £20 a week and the acting bug bit hard. Six months later he appeared alongside Emlyn Williams and alongside a young Richard Burton in a West End production of The Druid's Rest. The two Welsh boys from the mining valleys had found each other, and a friendship that would last the rest of Baker's life was forged.
After national service in the Royal Army Service Corps, Baker built steadily through film and television. His screen persona was unlike anything British cinema had seen from a leading man taciturn, surly, combustible, with a predilection for introspection and blunt speaking that was almost wilfully unromantic. He was not impossibly handsome and engagingly charming in the manner the era demanded. He was tough, gritty, dark. His roles in Hell Drivers (1957) and Yesterday's Enemy (1959) for which he received a BAFTA nomination for Best British Actor established him as one of the finest character actors in British cinema. The Guns of Navarone (1961) brought him international recognition alongside Gregory Peck, David Niven and Anthony Quinn.