Joseph Leo Cardijn (13 November 1882 – 24 July 1967) was a Belgian Roman Catholic cardinal and the founder of the Jeunesse ouvrière chrétienne (JOC) [Young Christian Workers]. Cardijn was best known for his lifelong dedication to social activism and working towards the improvement of the working class; since his ordination he made a particular focus of his life the effort to evangelize and bring the core messages of faith in the Gospel back to the working class, who he believed were neglected. He was not wrong in that assessment since old schoolmates working in the mines and mills believed the Church had abandoned them, which prompted Cardijn to found a social movement dedicated to this task despite the opposition that it faced.