This is a list of grand masters of the Constantinian Order of Saint George, a dynastic order of knighthood of the Catholic Church. Although it was founded by the Albanian Engjëlli family who claimed descent from the Byzantine Angelos dynasty in the 16th century, the order has throughout its existence maintained that it has its origin in Ancient Roman times, supposedly founded by Constantine the Great in the 4th century. Such an origin is otherwise regarded as being impossible, as there are no Roman or Byzantine records of such an institution ever existing and chivalric orders being completely unknown in the Byzantine world.

The founders of the order, the Engjëlli family, provided forged genealogies tracing their descent back to the 4th century, with grand masters covering the period from the Constantinian dynasty to the 16th century. These grand masters, maintained in modern official lists of grand masters, are mostly entirely invented, though some were real historical figures albeit with no connection to the chivalric order. In 1698, the position of grand master passed to the House of Farnese, and in 1731 it passed to the House of Bourbon-Two Sicilies, once rulers of the Kingdom of the Two Sicilies, to which the office still belongs. The line of grand masters within the House of Bourbon is divided today, with three separate claimants to the position. The Parmese branch of the Constantinian order split from the legitimate order in 1816 and is still maintained by the House of Bourbon-Parma. The legitimate order has itself been the subject of a succession dispute since 1960, which has in effect produced separate Spanish and Neapolitan orders, though neither recognizes the other as legitimate.

In addition to these succession disputes, claims to be the legitimate grand master of the Constantinian Order have also been forwarded by many impostors and pretenders to Byzantine titles and descent, on account of the order's invented Byzantine origins and its form of hereditary succession. As such, forgers who have claimed to represent "rightful" Byzantine emperors or dynasts have also often claimed the position of grand master. Several such "grand masters" remain active today.

Legendary grand masters (313–1570) The founding family of the Constantinian Order, the Angeli, made great genealogies that traced their descent back to the 4th century, as supposed descendants of Constantine the Great, with grand masters covering this period up until the 16th century. These grand masters are maintained in modern official lists of grand masters, but they are almost entirely invented figures. A handful of individuals are genuine historical figures, but they have no connection to the later chivalric order.

Historical grand masters (1545–present) House of Angeli (1545–1623)

No.PortraitNameTenureSuccession and NotesRef37Andrea AngeliPrince of MacedoniaDuke and Count of Drivasto and Durazzo 1545–1580(c. 35 years)First historically verified grand master, presumably the founder of the order. Recognized as grand master, among other titles, in 1545 by Pope Paul III.38Girolamo I AngeliPrince of Thessaly 1570–1591(21 years; with Andrea and then Pietro)Brother of Andrea Angeli, joint or rival grand master. Recognized in modern lists.39Pietro AngeliPrince of MacedoniaDuke and Count of Drivasto and Durazzo1580–1592(12 years)Nephew and designated successor of Andrea Angeli40Giovanni Andrea I AngeliPrince of MacedoniaDuke and Count of Drivasto and Durazzo1592 – 14 August 1623(31 years)(first tenure)Son and designated successor of Pietro Angeli

House of Caracciolo (1623–1627)

No.PortraitNameTenureSuccession and NotesRef41Marino CaraccioloPrince of Avellino14 August 1623 – 1627(4 years)Prominent Neapolitan noble and distant family relation, purchased the position of grand master from Giovanni Andrea I Angeli, who had considerable debts at the time

House of Angeli (1627–1698)

No.PortraitNameTenureSuccession and NotesRef40Giovanni Andrea I AngeliPrince of MacedoniaDuke and Count of Drivasto and Durazzo1627 – December 1634(7 years)(second tenure)Marino Caracciolo's succession was not recognized by other members of the Angeli family, and faced with a lack of widespread recognition and legal challenges, he gave back the position to Giovanni Andrea I Angeli–Majolino BisaccioniCount of Megaridi1632–1656(24 years)Previously grand chancellor, appointed as vice-grand master (grand master vicar) by Giovanni Andrea I Angeli in 1632, retaining this position after Giovanni Andrea I Angeli's death two years later, despite the two having fallen out. Recognized Angelo Maria Angeli's succession but did not relinquish his power until 1656.42Angelo Maria AngeliPrince of Macedonia and ThessalyDuke and Count of Drivasto and DurazzoDecember 1634 – 1678(44 years)Second cousin and designated successor of Giovanni Andrea I Angeli. Did not gain de facto control over the order until Majolino Bisaccioni relinquished his position in 1656.43Marco AngeliPrince of Macedonia and ThessalyDuke and Count of Drivasto and Durazzo1678–1679(1 year)Brother of Angelo Maria Angeli. Counted in official lists, but the historicity of his tenure is uncertain as he may have died before his brother.44Girolamo II AngeliPrince of MacedoniaDuke and Count of Drivasto and Durazzo1679–1687(8 years)Cousin and designated successor of Angelo Maria Angeli (or Marco Angeli)45Giovanni Andrea II AngeliPrince of MacedoniaDuke and Count of Drivasto and Durazzo1687 – 11 January 1698(11 years)Brother of Girolamo II Angeli. Last male member of his family.

House of Farnese (1698–1731)

No.PortraitNameTenureSuccession and NotesRef46Francesco FarneseDuke of Parma and Piacenza11 January 1698 – 26 February 1727(29 years, 1 month and 15 days)Purchased the position of grand master from Giovanni Andrea II Angeli. Documents of the sale specify that the order's hereditary succession from then on followed the descendants of Francesco Farnese. Further justified his claim to the order through matrilineal (female-line) descent from Isaac II Angelos. Rights confirmed by Pope Innocent XII and Holy Roman Emperor Leopold I.47Antonio FarneseDuke of Parma and Piacenza26 February 1727 – 20 January 1731(3 years, 10 months and 25 days)Brother of Francesco Farnese. Last male member of his family.

House of Bourbon-Two Sicilies (1732–present)

No.PortraitNameTenureArmsSuccession and NotesRef48Charles III of SpainKing of SpainKing of Naples and SicilyDuke of Parma and Piacenza6 April 1732 – 16 October 1759(27 years, 6 months and 10 days)Son of Elisabeth Farnese, niece of Francesco Farnese and Antonio Farnese. Legitimate senior heir of Antonio Farnese. Formally invested as grand master by a group of Constantinian knights on 6 April 1732. Confirmed as grand master by Pope Clement XII on 12 May 1739.49Ferdinand I of the Two SiciliesKing of the Two Sicilies16 October 1759 – 4 January 1825(65 years, 2 months and 19 days)Charles III became king of Spain in 1759, and due to agreements prohibiting the unification of the Spanish and Sicilian crowns, designated his third son Ferdinand as heir to his Italian possessions and as the new Constantinian grand master as "First Born Legitimate Farnese heir". Ferdinand's succession as grand master was confirmed by Pope Clement XIII on 18 December 1763.50Francis I of the Two SiciliesKing of the Two Sicilies4 January 1825 – 8 November 1830(5 years, 10 months and 4 days)Son of Ferdinand I51Ferdinand II of the Two SiciliesKing of the Two Sicilies8 November 1830 – 22 May 1859(28 years, 6 months and 14 days)Son of Francis I52Francis II of the Two SiciliesKing of the Two Sicilies22 May 1859 – 27 December 1894(35 years, 7 months and 5 days)Son of Ferdinand II. Francis II was the last king of the Two Sicilies, being deposed in 1861 during the unification of Italy. Francis II retained his position as grand master after his deposition.53Prince AlfonsoCount of Caserta27 December 1894 – 26 May 1934(39 years, 4 months and 29 days)Brother of Francis II and heir to his claims and prerogatives54Prince Ferdinand PiusDuke of CastroDuke of Calabria26 May 1934 – 7 January 1960(25 years, 7 months and 12 days)Son of Alfonso

Disputed succession (1960–present) The leadership of the Constantinian Order has been disputed since the death of Ferdinand Pius in 1960. The immediate male primogeniture heir of Ferdinand Pius was Infante Alfonso, the son of Ferdinand’s eldest younger brother Carlos. Carlos married María de las Mercedes, Princess of Asturias, the heir presumptive to the throne of Spain, in 1901. Before the marriage, the Spanish minister of Justice stated explicitly in the Cortes (Parliament) that there was no need for Prince Carlos to renounce his "eventual succession to the crown" of the Two Sicilies, and that no such renunciation would be valid, although a renunciation of former nationality was required to become a Spanish citizen. Since the treaty of Vienna of 1737 and the treaty of Naples of 1759, followed by the Pragmatic Decree of 1759, it was required that the crowns of Spain and Two Sicilies should not be united in the same person and in such circumstances the Italian sovereignties should be abdicated to the next prince in line. Nonetheless, Prince Carlos’s father, the Count of Caserta, drew up a precaution the Act of Cannes to ensure that should the Princess of Asturias become queen and therefore her husband king consort, and should Prince Ferdinand Pius die without surviving male issue, the eventual succession to the crown would pass to the next prince in line. The pragmatic decree of Charles III of Spain of 1759 and the Two Sicilies royal constitution in force in 1860 did not require a renunciation in any other circumstances. Nevertheless, Ferdinand Pius' and Carlos' younger brother, Ranieri, began to regard himself as Ferdinand's heir. The grand mastership of the Constantinian Order is a separate succession governed by its own statutes confirmed by the Papal bull Militantis Ecclesiae of 1718 and was defined on 8 March 1796 by Ferdinand IV and III (from 1815 Ferdinand I of the Two Sicilies) as a separate and distinct dignity from the Two Sicilies crown. It was this separate nature that enabled it to survive the abolition of the kingdom of the Two Sicilies and obtain the public support of Pope Pius X and Pope Benedict XV in the early 20th century. There was no mention of the Constantinian Order or its grand mastership in the Act of Cannes and in 1929 the Count of Caserta asked Prince Carlos to assume the grand mastership to ensure its Catholic nature, since the Lateran Treaty had changed the close relationship hitherto enjoyed by the heads of the Two Sicilies royal house with the Vatican. Prince Carlos, however, declined as at that time he was a serving Captain-General in the Spanish army with multiple public responsibilities in Spain.

In Naples, in 1960, where the then vice-grand chancellor of the Order, Achille Di Lorenzo, resided, there was some opposition towards the idea of Alfonso succeeding Fredinand as it was feared that he would introduce Spanish elements into what was otherwise viewed as a distinctly Neapolitan institution. Not only was Ranieri supported by many of the Constantinian Order's members, but Ferdinand Pius also made it clear that he wished Ranieri, and not Alfonso, to succeed him. This was by no means commonly supported as correspondence on the subject in the Italian Rivista Araldica demonstrates. At the same time as Ranieri was proclaimed grand master in Naples after Pius' death, Alfonso was proclaimed grand master in Madrid; Alfonso had at no point doubted his own rights and had not even been informed by his father that they had been "renounced" given that Carlos himself considered his supposed renunciation irrelevant.