Pius XI announced the establishment of the feast of Christ the King in an encyclical, Quas primas, published in December 1925. In its introduction he reflects on the significance of the year which is coming to an end. It is interesting to revisit the context to learn more about the feast which finishes our liturgical year. The year 1925 was a jubilee year, and at Pius XI’s insistence there was an exhibition about the work of missionaries held in the Vatican, which allowed visitors to see “how many countries have been won to the Catholic name through the unremitting labour and self-sacrifice of missionaries, and the vastness of the regions which have yet to be subjected to the sweet and saving yoke of our King”. It was a time when the desire to convert whole countries to Christianity was clearly regarded as evidence of zeal, not colonialism.