Ruth Ellis was born Ruth Neilson in the coastal town of Rhyl, Wales on 9 October 1927. The original family name was Hornby but her father, a cellist from Manchester, used the stage name Arthur Neilson. Much of his work was playing music on Atlantic cruise liners. Her mother, Elisaberta, was half French, half Belgian and had fled to the UK during the World War I German invasion of Belgium. The shortsighted, bespectacled Ellis was one of five children who were raised as strict Catholics. As a young girl, Ellis loved clothes and aspired to make something out of her life.
At the height of the Blitz (the sustained bombing of the United Kingdom by Nazi Germany between 7 September 1940 and 16 May 1941), the family moved to London in 1941. Ellis was 14 years old and left school to begin working as a waitress. By 16, she was starting to make the most of her looks, dyeing her dark hair blonde, and was determined to live life to the fullest. At age 17, she had a brief affair with a French-Canadian soldier, named Clare, who was a married man. She fell pregnant soon after Christmas 1944 and gave birth to a son, Clare Andrea, whom everyone called Andy, on 15 September 1945. Clare continued to pay maintenance and visit Ellis and her son, who were living with her parents until, abruptly, he returned to his family in Canada, sending her a bunch of red roses and a letter informing her he was gone. Ellis was distraught and felt abandoned. Her faith in men had been badly shaken, and she would never see him again.
Having to support a young son on her own, Ellis found work in factories and had various clerical jobs. These were not very well paid and she decided to try her hand at something more lucrative. She began some modelling work and then became a nightclub hostess, finally earning a significant wage.
At the age of 23, she married George Johnson Ellis on 8 November 1950. Her husband, a 41-year-old divorcée with two sons, was a dentist and had been one of her nightclub customers. Sadly, it transpired that George was an alcoholic and prone to violence when drunk. Ellis became convinced he was having an affair, her behaviour towards him becoming possessive and jealous. The marriage quickly began to show signs of strain and when her second child, Georgina, was born in 1951, George refused to acknowledge the child as his own. Ellis could not remain in the situation any longer and the couple soon separated. Ellis went to live with her parents and returned to work as a nightclub hostess.