After the extinction of the Order of the Temple decreed in 1312 by Pope Clement V, all the Templars’ possessions were to be transferred to the Hospitallers, except those of Portugal, Castile, Aragon, and Mallorca, which were to remain in the possession of the respective Crowns until their fate was decided.
In order to avoid their extinction and the confiscation of their property, King Dinis established the Militia of Our Lord Jesus Christ Order in 1319, to which he transferred the rights belonging to the former Portuguese Templars, namely Castelo Branco, Longroiva, Tomar, and Almourol, as well as all the castles, movable and immovable property, rights, jurisdictions, honours, men and vassals that had belonged to the suppressed order.
Based on the need to defend Portugal against Muslim domination, which was geographically close to the limits of Portuguese territory, after several years of dialogue with the Holy See, King Dinis, with a bull from Pope John XXII, dated 19th March 1319, instituted the Ordo Militae Jesu Christi, or Military Order of Our Lord Jesus Christ, which incorporated the members, property, and privileges of the now-defunct Order of the Temple.
Like the Order of the Temple in Portugal, the Order of Christ followed the Cistercian rule, and the abbot of Alcobaça remained its spiritual assistant. The habit of the knights of the Order of Christ was also similar to that of the Knights Templar, and was white with a red cross, although it was different: while the Templar cross had curved arms, the cross of the Order of Christ has straight arms with serifs on the ends and white in the middle.
Initially based in Castro Marim, near the estuary of the Guadiana River, the headquarters of the Order of Christ only returned to the city of Tomar in 1357, where it remained permanently.
Thoroughly reformed by Prince Henry the Navigator, who became its administrator from 1417, the Order of Christ came to have as its main mission the discovery of new lands and new seas.