Rome, Sassari, the world: The birth of World Mission Sunday in five stages

Pope Pius XI approved the establishment of World Mission Sunday on April 14, 1926, to integrate missionary prayer, awareness, and financial support into parish life. The decision followed a proposal from the Pontifical Society for the Propagation of the Faith and drew on missionary activity occurring within local communities, such as the diocese of Sassari in Sardinia.

The move built upon earlier directives from Pope Benedict XV, who in his 1919 Apostolic Letter Maximum illud urged the Church to separate evangelization from national interests and to train local clergy. Pope Pius XI expanded these efforts in 1922 through the motu proprio Romanorum Pontificum, which moved the Society for the Propagation of the Faith to Rome and granted pontifical recognition to the Missionary Societies. This change ensured that funds raised for missions would serve global needs rather than specific national affiliations.