José María Arizmendiarrieta was a Spanish Catholic priest (1915–1976) who became a transformative figure in the Basque Country through his promotion of worker-owned enterprises. Born in Markina-Xemein, he served as a curate in the industrial town of Mondragon from 1941 until his death. He is most recognized for establishing the cooperative model that evolved into the Mondragon Corporation, a major global social economy group. Driven by principles of social justice and human dignity, he sought to improve the lives of workers through self-managed business structures.