Mengenen is believed to have been born circa 1922 (no record was kept of the exact year) in Mount House Station, eastern Kimberley, Western Australia. His father, Jack Dale, was of Scottish descent, while his mother, Moddera, was indigenous aboriginal and member of the Komaduwah clan who had traditionally lived on the land held by the Mount House Pastoral Lease. Usually, mixed race children were killed at birth in Western Australia, but Mengenen's life was spared. His father was a violent man, who was known to have murdered indigenous laborers in the area. He once shot Mengenen, his own son, in the leg when he tried to run away. After Mengenen's father died an early, violent death, Mengenen fled into the rural Kimberley with his Ngarinyin mother, Moddera, who raised him according to indigenous traditions. He avoided Australian authorities, who would have placed in government-operated schools. In 1942, Mengenen survived the Japanese attack on Broome, Western Australia, narrowly avoiding strafing from a plane. His friend was killed in the raid.