The Sacred Military Constantinian Order of Saint George (, ), also historically referred to as the Imperial Constantinian Order of Saint George and the Order of the Constantinian Angelic Knights of Saint George, is a dynastic order of knighthood of the House of Bourbon-Two Sicilies. Currently, the grand magistry of the order is disputed among the two claimants to the headship of the former reigning House of Bourbon-Two Sicilies as heirs of the House of Farnese, namely Prince Pedro and Prince Carlo. The order was confirmed as a religious-military order in a 1718 papal bull owing to a notable success in liberating Christians in the Peloponnese. Alongside the Sovereign Military Order of Malta it is the sole international Catholic Order which still has this status today. Although it is not an order of chivalry under patronage of the Holy See, membership is restricted to practising Catholics.