David Allen (1830-1903) started a printing firm in Belfast in 1857. This would be the beginning of a family advertising and printing business that would last over 100 years. Run by the family, at least up to 1966. Originally printing Theatrical Posters, the company would expand to Dublin, Liverpool, Glasgow, Harrow, London and Brentford. Perhaps best known in the stamp world for their World War I posters and poster stamps. Several generations of Allens ran the business but by 1966 the company had become David Allen Holdings Ltd. They are now based in Brentford but are now ultimately owned by the French advertising family Decaux of JCDecaux fame.