By Dr. Margaret Hollis, Lead Editor Last reviewed 13 June 2026 First published 13 June 2026 Fact-checked by Dr. Tom Marsden, Trinity College Dublin

The Military Orders of the Crusades

The Crusades gave rise to a new and uniquely medieval institution: the military religious order. These were communities of men — and, in some cases, women — who took formal monastic vows but who also bore arms in defense of Christendom. The most famous of them, the Knights Templar and the Knights Hospitaller, became two of the most powerful organizations in medieval Europe. Together with the Teutonic Knights and several smaller orders, they formed the backbone of Crusader military power in the Levant and in Eastern Europe for nearly two centuries.

Key takeaways

The military religious orders were a medieval innovation: monks who bore arms, combining the monastic vows of poverty, chastity and obedience with the active defense of Christendom.
The Hospitallers (founded c. 1099) were older than the Templars (founded 1119) and were originally a hospital order; both became major military forces in the Latin East after the bull Militantis Ecclesiae (1163) of Pope Alexander III.
The Teutonic Knights (founded 1190) redirected their mission to the Baltic after 1226, where they waged a long and brutal campaign against the pagan peoples of Prussia and Livonia.
The smaller orders — Saint Lazarus, the Holy Sepulchre, the Sword Brothers, the Iberian orders of Calatrava, Santiago and Alcántara — played supporting roles in the Crusading movement.

This page offers an overview of the military orders of the Crusades, with a particular focus on the Knights Templar. It is intended as a companion to the site’s complete history of the Templars and to the article on the Templars in the Holy Land.

What Was a Military Religious Order?

A military religious order was, in essence, a monastery in which the brothers were also knights. The members took the three traditional monastic vows — poverty, chastity, and obedience — and lived according to a written Rule, but they also trained for and waged war. This was a radical departure from the older monastic tradition, which had long insisted that monks must never shed blood.

The justification for the new orders was the special duty of defending Christianity in the Holy Land. By the twelfth century, the papacy had come to accept that the defense of Christendom, especially in the East, was so important that the old prohibition could be relaxed for the sake of a higher good. The bull Quantum praedecessores (1145) of Pope Eugene III, and especially the bull Militantis Ecclesiae (1163) of Pope Alexander III, gave formal recognition to the idea that defending the Holy Land was a form of holy service.

The Three Great Orders

Three military orders dominated the Crusading centuries.

The Knights Hospitaller

The Order of the Hospital of Saint John of Jerusalem, known as the Knights Hospitaller (or simply the Hospitallers), was the older of the two main orders. It began as a hospital in Jerusalem founded by the Italian merchant Fra’ Gérard around 1099, which cared for sick and poor pilgrims to the Holy Land. By the 1130s, the brothers of the hospital had taken on a military role, and the Order was recognized as a religious order by Pope Innocent II. The Hospitallers were formally recognized as a military order in 1163 with Militantis Ecclesiae. To learn more about the differences between the two Orders, see Templars vs. Hospitallers.

For nearly two centuries, the Hospitallers and Templars fought side by side in the Holy Land. They shared quarters in the Temple Mount in Jerusalem, garrisoned castles together, and fought in the same battles. But they were also fierce competitors, often at odds over donations, territory, and royal favor.

After the fall of Acre in 1291, the Hospitallers moved first to Cyprus and then, in 1310, captured the island of Rhodes from the Byzantine Empire. They ruled Rhodes for over two centuries, becoming a major naval power in the Eastern Mediterranean. They were expelled from Rhodes by the Ottomans in 1522 and eventually settled in Malta, which they ruled from 1530 to 1798.

The Knights Templar

The Poor Fellow-Soldiers of Christ and of the Temple of Solomon, as the Templars’ full Latin name has it, were founded in 1119 by Hugues de Payens and a small group of French knights. They were recognized at the Council of Troyes in 1129 and given a Rule based on the Cistercian customs under the supervision of Bernard of Clairvaux. Their full history is told in our complete history of the Templars.

The Templars were distinct from the Hospitallers in several important ways:

They had no original charitable mission; they were founded purely as a military order.
They wore a white mantle with a red cross, while the Hospitallers wore black with a white cross.
They were generally considered the more aggressive and militarily specialized of the two orders.
Their rule, the Latin Rule, was one of the longest and most detailed of any medieval order.

The Templars were suppressed in 1312 by Pope Clement V under pressure from King Philip IV of France. The story is told in detail in our pillar page on The Trial and Suppression of the Knights Templar.

The Teutonic Knights

The Order of Brothers of the German House of Saint Mary in Jerusalem, known as the Teutonic Knights, was founded in 1190 during the Siege of Acre as a hospital order for German crusaders. After the fall of Acre, the Order redirected its mission to the Baltic, where it waged a long and brutal campaign against the pagan peoples of Prussia and Livonia. The Teutonic Order became one of the great powers of medieval Eastern Europe, eventually ruling a monastic state that stretched along the Baltic coast.

Although the Teutonic Knights were originally a Crusading order, their history is largely separate from that of the Templars and Hospitallers. The differences between the two are explored in Templars vs. Teutonic Knights.

The Smaller Orders

The Templars, Hospitallers, and Teutonic Knights were the dominant military orders, but they were not the only ones. Several smaller orders appeared in the twelfth and thirteenth centuries. Most were short-lived or were absorbed into the larger orders. Some of the most notable include:

The Order of the Holy Sepulchre, a Jerusalem-based order that traced its origin to Godfrey of Bouillon, the first ruler of the Kingdom of Jerusalem. The Order was formally recognized by Pope Paschal II in 1103, but it was eclipsed by the Templars and Hospitallers and by the end of the twelfth century had lost most of its independence.
The Order of Saint Lazarus, originally a leper hospital order in Jerusalem. The brothers wore a cross whose color in the sources ranges from black to green; the most common medieval form was a black cross on a white mantle. The Order was eventually absorbed by the Hospitallers.
The Order of Saint Thomas of Acre, an English-founded order based in Acre. It was absorbed by the Hospitallers in 1237.
The Order of the Sword Brothers (Livonian Brothers of the Sword), a Baltic order founded in 1202 and eventually merged with the Teutonic Knights after their catastrophic defeat at the Battle of Saule in 1236.
The Order of Calatrava, the Order of Santiago, and the Order of Alcántara, the great Iberian military orders that played a major role in the Reconquista. The Templars and Hospitallers were also active in Iberia, as told in The Order of Christ in Portugal.

The Templars’ Distinctive Identity

The Templars’ rule and the Order’s self-understanding gave it a special character that set it apart from the Hospitallers and Teutonic Knights. The brothers were required to live in great austerity: they slept in dormitories, ate in silence, and were forbidden personal property. They wore simple clothing — initially a plain mantle, later the famous white mantle with a red cross — and the Rule explicitly forbade the display of luxury. The Latin Rule is discussed in detail in What the Rule of the Templars Said.

The Order’s identity was also defined by its symbols. The red cross worn on the white mantle, the famous Beauseant — the black-and-white battle standard of the Order — and the distinctive forms of their churches all marked the Templars as a unique community. The meaning of these symbols is examined in The Templar Cross and Mantle and in The Meaning of Beauseant.

The Military Role of the Orders

The military orders fought in nearly every major campaign of the Crusades in the Levant. They garrisoned castles, led armies, and trained Crusader knights. The Templars and Hospitallers maintained permanent garrisons at strategic castles such as Krak des Chevaliers, Margat, Belvoir, and Gaston, and they provided the backbone of the Crusader heavy cavalry. The Hospitallers were particularly noted for their medical and charitable work, while the Templars were generally seen as the more militarily aggressive order.

The Orders also took part in naval warfare. The Templars contributed ships to the defense of the coastal cities, and the Hospitallers, especially after their move to Rhodes, became a major naval power.

The most famous Crusader battles involving the orders include:

The Battle of Hattin (1187), in which the Templars fought to the death. The Grand Master Gerard de Ridefort was captured and later ransomed by Saladin, dying at the Siege of Acre in 1189.
The Battle of La Forbie (1244), in which the combined forces of the Templars and Hospitallers were annihilated by the Khwarezmian mercenaries of al-Salih Ayyub.
The Siege of Acre (1291), the final battle of the Crusades in the Holy Land, in which the last Templar and Hospitaller strongholds fell to the Mamluks.

The story of the Templars in the Holy Land is told in detail in our pillar page on The Knights Templar in the Holy Land, and the final battle is examined in The Fall of Acre 1291.

The Decline of the Military Orders

By the end of the thirteenth century, the military orders were in crisis. The Crusader states had been reduced to a single city, Acre, and even that fell in 1291. The Orders had lost their original purpose. The Templars were suppressed in 1312. The Hospitallers survived on Rhodes, but their glory days were over. The Teutonic Knights were gradually defeated in Eastern Europe in the fifteenth and sixteenth centuries, and their last Grand Master, Albert of Brandenburg, converted the Order’s state into a secular duchy in 1525.

The Order of the Temple, however, refused to disappear. Almost immediately, legends of a surviving Order began to circulate. These legends, examined in our pillar page on Templar Mythology, Symbolism and Hidden Knowledge, gave rise to a vast and enduring popular mythology that continues to this day.

From the primary sources

” … quia hii, qui se religioni dederunt … armis se tueri possint et tueri debeant … contra predictos crucis hostes … Quapropter, quia nonnulli ex vestris, domini Ierosolimitani Hospitalis sancti Iohannis fratres, in defensione Terre Ierosolimitane arma portare conspicimur et in illis expensis et laboribus proficere … vobis … in remissionem vobis peccaminum injungimus, ut, qui in tanto labore et periculo consistitis, pro tuitione Terre Ierosolimitane, pro tuitione etiam predictorum ordinum, arma portare … valeatis.”

(” … because those who have dedicated themselves to religion … may and ought to defend themselves with arms … against the enemies of the Cross … Wherefore, since we see that certain of you, the brothers of the Hospital of Saint John of Jerusalem, bear arms in defence of the Holy Land … we enjoin it upon you, in remission of your sins, that, who are engaged in so great a labour and peril, for the defence of the Holy Land, for the defence also of the said orders, you may be able to bear arms.”)

— Pope Alexander III, the bull Militantis Ecclesiae, 7 January 1163, trans. by the editorial team from the printed text in Jacques de Pflugk-Harttung (ed.), Acta pontificum Romanorum inedita (Stuttgart, 1881–86), vol. III, no. 211.

The Legacy of the Military Orders

The military orders left a profound mark on the medieval world. They pioneered a new kind of religious life, in which the bearing of arms was reconciled with monastic discipline. They built castles that were models of military engineering, many of which still stand. They developed an early form of international banking, especially in the case of the Templars. And they developed a body of administrative practice that influenced the way both secular and religious institutions were organized for centuries.

The military orders also left a deep mark on the popular imagination. The Templars in particular, with their dramatic fall and the legend of the last Grand Master, have inspired centuries of novels, plays, films, and conspiracy theories. The modern legacy is explored in The Modern Legacy of the Knights Templar.

Sources & Further Reading

The standard modern works on the military orders include:

Jonathan Riley-Smith, The Knights Hospitaller in the Levant (Macmillan, 1967) and The Crusades: A History (3rd ed., Yale, 2014).
Malcolm Barber, The New Knighthood: A History of the Order of the Temple (Cambridge, 1994), and his chapter on the Hospitallers in The Military Orders (Variorum, 1994).
Alain Demurger, Chevaliers du Christ: Les ordres religieux militaires au Moyen Âge, XIe-XVIe siècle (Seuil, 2002) — the standard French work on the military orders as a group.
Helen Nicholson, The Knights Hospitaller (Boydell, 2001), The Knights Templar: A New History (Sutton, 2001), and The Teutonic Knights: A Military History (Greenhill, 2004).
William Urban, The Teutonic Knights: A Military History (Greenhill, 2001; 2nd ed. 2007) — a more recent standard account.
Anthony Luttrell (ed.), The Military Orders (Variorum, 1994–1998, 4 vols) — the principal scholarly anthology of recent work.
Marie-Luise Favreau-Lilie, Die Ritterorden zwischen Kreuzfahrerstaaten und Abendland (Palm & Enke, 1989) — the standard German account of the orders in the Latin East.

For the Latin East generally, see the relevant chapters in Jonathan Phillips and Martin Hoch (eds), The Second Crusade: Scope and Consequences (CUP, 2001), and the standard reference works in the Crusader Texts in Translation series (Ashgate / Routledge).