JONS was founded on 10 October 1931 as the fusion of the group around La Conquista del Estado (The Conquest of the State) of Ramiro Ledesma Ramos and the Juntas Castellanas de Actuación Hispánica (Castilian Councils of Hispanic Action) of Onésimo Redondo. JONS, whose leadership was the Central Executive Triumvirate, began as a small organization, primarily amongst students in Madrid as well as workers and peasants in and around Valladolid. Its followers were called jonsistas.
In 1933, JONS experienced a period of expansion and started publishing a theoretical journal, JONS.
Amongst other endeavors, the organisation engaged in trade union work in Castile. In January 1933, Gutiérrez Palma set up a transport-workers union in Valladolid. Later the same year, JONS founded the Agrarian Trade Union Federation. In six months, it had set up 175 trade unions, which together claimed around 3,000 members. During that year, Onésimo Redondo returned from exile in Portugal and restarted the publication Libertad.