The World Day of Peace is an annual celebration by the Catholic Church, dedicated to universal peace, held on 1 January, the Solemnity of Mary, Mother of God. Pope Paul VI established it in 1967, being inspired by the encyclical Pacem in Terris of Pope John XXIII and with reference to his own encyclical Populorum Progressio. The day was first observed on 1 January 1968.
