Historical sources of the Crusades: pilgrimages and exploration include those authors whose work describes pilgrimages to the Holy Land and other explorations to the Middle East and Asia that are relevant to Crusader history. In his seminal article in the Catholic Encyclopedia, Dominican friar and historian Bede Jarrett (1881–1934) wrote on the subject of Pilgrimage,Jarrett, Bede (1911). "Pilgrimages". In Herbermann, Charles (ed.). Catholic Encyclopedia. 12. New York: Robert Appleton Company. and identified that the "Crusades also naturally arose out of the idea of pilgrimages." This was reinforced by the Reverend Florentine Stanislaus Bechtel in his article ItinerariaBechtel, Florentine Stanislaus (1910). "Itineraria". In Herbermann, Charles (ed.). Catholic Encyclopedia. 8. New York: Robert Appleton Company. in the same encyclopedia. Pilgrims, missionaries, and other travelers to the Holy Land have documented their experiences through accounts of travel and even guides of sites to visit. Many of these have been recognized by historians, for example, the travels of ibn Jubayr and Marco Polo. Some of the more important travel accounts are listed here. Many of these are also of relevance to the study of historical geography and some can be found in the publications of the Palestine Pilgrims' Text Society (PPTS) and Corpus Scriptorum Eccesiasticorum Latinorum (CSEL), particularly CSEL 39, Itinerarium Hierosolymitana. Much of this information is from the seminal work of 19th-century scholars including Edward Robinson, Titus Tobler and Reinhold Röhricht.Schein, Sylvia. "Pilgrimage". The Crusades - An Encyclopedia. pp. 957-963. Retrieved 28 July 2020 Recently, the Independent Crusaders Project has been initiated by the Fordham University Center for Medieval StudiesFordham Medieval Digital Projects. providing a database of Crusaders (with sources identified) who traveled to the Holy Land independent of military expeditions.

Overview Authors who wrote about their travels or pilgrimages to the Holy Land or to the land of the Mongols were prevalent through the 16th century, and lasted into the 19th century. Some were accounts by merchants trading with non-European partners. Notable early travelers include Marco Polo, ibn Battūta, Odoric of Pordenone, John Mandeville, Bertrandon de la Broquière, Marino Sanuto the Younger, and Felix Fabri. Later travelers to include diplomats, were Jean Thenaud, Evliya Çelebi, and Richard Burton. Surveys of the Holy Land were sponsored by the Palestine Exploration Fund, beginning in 1864, including those by Claude R. Conder, Edward Hull, and Herbert Kitchener.Les Archives de littérature du Moyen Âge (ARLIMA). "Récits de voyage et traités géographie".

Collections of those works, as well as Crusader-era accounts that are in the Palestine Pilgrims' Text Society (PPTS) library (1886–1897), the Hakluyt Society (founded 1846) and the Societé de l'Orient Latin (founded 1875 by Paul Riant) that include Itinera hierosolymitana et descriptiones terrae sanctae... (1879) by Titus Tobler and Auguste Molinier; and Itinéraires à Jérusalem et descriptions de la Terre Sainte... (1882) by Henri-Victor Michelant and Gaston Raynaud. Other collections include Recueil de voyages... (1882–1916) by Charles Henri Auguste Schefer and Henri Cordier; Early Travels in Palestine (1848) by Thomas Wright; Cathay and the Way Thither (1866) by Henry Yule; and those identified in Titus Tobler's Bibliographia Geographica Palestinæ.

Pilgrimages before the Crusades Descriptions of pilgrims to the Holy Land began long before the Crusades, as early as the 3rd century AD.

Origen. Origen (c. 184 – c. 253), a Christian scholar who wrote In Joannem (Commentary on John) about the desire of Christians to search after the footprints of Christ.Baldwin, M. W. (1969). A History of the Crusades. Volume One: The First Hundred Years. p. 69.

Eusebius. Eusebius of Caesarea (before 265 – after 339), a historian of Christianity published in PPTS I.1.Bacchus, Francis Joseph (1909). "Eusebius of Caesarea" . In Herbermann, Charles (ed.). Catholic Encyclopedia. 5. New York: Robert Appleton Company.

Historia Ecclesiastica (Church History), where a Cappadocian bishop Alexander who visited the Holy Land in the 3rd century is identified. Life of Constantine. Includes a description of Saint Helen's pilgrimage to the Holy Land in 326–327. Excerpted in The Churches of Constantine at Jerusalem. An earlier Christian scholar Origen (c.184 – c. 253) wrote In Joannem (Commentary on John, Vol VI) about the desire of Christians to search after the footprints of Christ. In PPTS I.1.

Itinerary of the Bordeaux Pilgrim. Itinerary from Bordeaux to Jerusalem (Itinerarium Burdigalense), an anonymous account of a pilgrimage to the Holy Land in 333–334, with travels beginning shortly after that of Saint Helen. This is the oldest known Christian itinerarium. In PPTS I.2.Bechtel, Florentine (1910). "Itineraria" . In Herbermann, Charles (ed.). Catholic Encyclopedia. 8. New York: Robert Appleton Company.

Egeria. Egeria (fl. 380s), also known as Etheria or Aetheria, was a Spanish pilgrim from the 4th century.Vikan, Gary. "Egeria". Oxford Dictionary of Byzantium. p. 679.

Itinerarium Egeriae (Pilgrimage of Aetheria). An account of Egeria's pilgrimage to the Holy Land once attributed to Saint Silvia of Aquitaine. In PPTS I.3.

Saint Jerome. Saint Jerome (c. 347–420), a Latin historian wrote of the early pilgrims to Jerusalem, some of which were published in PPTS I.4, I.5.Saltet, Louis (1910). "St. Jerome". In Herbermann, Charles (ed.). Catholic Encyclopedia. 8. New York: Robert Appleton Company.

Epistotlae, De Viris Illustribus and Liber Paralipumenon. An account of pilgrimages that began in the early 3rd century AD with a bishop of Caesarea named Fermilian. Pilgrimage of Holy Paula. A personal account of his travels with Saint Paula of Rome (347–404) and her daughter Eustochium to the Holy Land, settling in Bethlehem. Their correspondence with Saint Marcella (325–410) has been published as Letter of Paula and Eustochium to Marcella.

Socrates of Constantinople. Socrates of Constantinople (c. 380 – after 439), also known as Socrates Scholasticus, a Greek historian.Urbainczyk, Theresa (1997). Socrates of Constantinople, University of Michigan Press, Ann Arbor.

Historia Ecclesiastica. A continuation of the work of Eusebius of Caesarea by the same title, Historia Ecclesiastica covers the church from 305 to 439, including the pilgrimage of Saint Helena, mother of Constantine the Great, and her finding relics of the True Cross, including nails and the Titulus Crucis.

Saint Eudocia. Saint Eudocia (c. 401 – 460), a Byzantine empress married to Theodosius II who went on a pilgrimage to Jerusalem in 438–439, returning with numerous holy relics. Her activities on her pilgrimage are recorded in Nicephoros Callistus' 14th-century work Historia Ecclesiastica.Chisholm, Hugh, ed. (1911). "Eudocia Augusta". Encyclopædia Britannica. 9 (11th ed.). Cambridge University Press. p. 881.

Descriptions of the Holy Land in the 5th and 6th Centuries. Numerous works dating from 440 to 570 describe the geography, topography, and buildings in the Holy Land.Runciman, Steven (1969). "Chapter II.D. The Pilgrimages to Palestine before 1091 ." In Setton, Kenneth M.; Baldwin, Marshall W. (eds.). A History of the Crusades: I. The First Hundred Years. Madison: The University of Wisconsin Press. pp. 68-80. These include: The Epitome of S. Eucherius (440); The Breviary of Jerusalem (530); Theodosius' De situ terrae sanctae, or Topography of the Holy Land (530); The Buildings of Justinian, by Procopius (500 – after 565); and The Holy Places Visited by Antoninus Martyr (c. 570), the so-called anonymous pilgrim of Piacenza. Both the Breviary and Antoninus Martyr describe the crown of thorns present in a “Basilica of Mount Zion.” In PPTS II.1–II.4.

Cosmas Indicopleustes. Cosmas Indicopleustes (fl. 6th century) was a Greek merchant and later hermit from Alexandria who made several voyages to India during the reign of Justinian.Chisholm, Hugh, ed. (1911). "Cosmas (of Alexandria)". Encyclopædia Britannica. 7. (11th ed.). Cambridge University Press. p. 937. His work Christian Topography contains some of the earliest and most famous world maps.Cosmas, I., McCrindle, J. Watson. (1897). [Kosma aigyptiou monachou Christianikē topographia] =: The Christian topography of Cosmas, an Egyptian monk. London: Printed for the Hakluyt Society.

Vita Genovefae Virginis Parisiensis. The anonymous Vita Genovefae Virginis Parisiensis was a life of Saint Geneviève of Paris written c. 520. The work relates an incident where Saint Symeon Stylites (died 459) on his pillar in Aleppo, asked for news of Geneviève and sent her a letter.Andrew Alphonsus MacErlean (1909). "St. Genevieve". In Catholic Encyclopedia. 6. New York.Arculf and Adomnán. Arculf (fl. late 7th century), a Frankish bishop who toured the Holy Land c. 680. Adomnán (c. 624–704) was a Scottish abbot who wrote about sacred places based on the work of Arculf. The accounts contain the second oldest known map of Jerusalem (the oldest being the Madaba Map). In PPTS III.1.

Pilgrimage of Arculfus in the Holy Land (about the year A.D. 670). De locis sanctis (Concerning Sacred Places), a work by Adomnán based on Arculf's account.Saint Wlphlagio. De Sancto Wlphlagio (7th century), a priest in the Holy Land.

Commentatious historicus. A work discussing 7th-century pilgrims including Vulphy of Rue, was also noted by Arculf, and Saint Bercaire (died 696). Bercaire (Bercharius), the founder of the abbey of Montier-en-Der, was accompanied by a Waimer, one of the murderers of Saint Leodegar, and he returned with valuable relics that he donated to Montier-en-Der and Châlons-sur-Marne. Three centuries later, abbot Adso of Montier-en-Der (died 992), hagiographer of Bercaire, embarked on a similar pilgrimage to Jerusalem accompanying a pentinent Hilduin II, Count of Arcis-sur-Aube, but died en route.Omont, Henri, Persée, Parcourir les Collections. "Catalogue de la bibliothèque de l'abbé Adson de Montier-en-Der (992)". Retrieved 1 August 2020.Grey, Francis (1907). "Adso" . In Herbermann, Charles (ed.). Catholic Encyclopedia 1. New York: Robert Appleton Company.Saint Willibald. Saint Willibald (c. 700 – c. 787), an English bishop who traveled to Holy Land sometime between 720 and 740.Mershman, Francis (1912). "Sts. Willibald and Winnebald". In Herbermann, Charles (ed.). Catholic Encyclopedia. 15. New York: Robert Appleton Company.

Hodoeporicon (itinerary) of Saint Willibald. An account of the travels of Willibald, dictated to an Anglo-Saxon nun named Huneberc. Willibald was the first known Englishman to travel to the Holy Land. His father Richard the Pilgrim attempted the trip but died en route. In PPTS III.2.Commemoratorium de Casis Dei vel Monasteriis. Commemoratorium de Casis Dei vel Monasteriis is a report from 808 sent to Charlemagne tabulating all churches, monasteries, and hospices in the Holy Land. Its purpose was to allow the emperor to expeditiously distribute alms. In Descriptiones Terrae Sanctae ex saeculo VIII., IX., XII. et XV (1874) by Titus Tobler.

Peregrinatio Frotmundi. Peregrinatio Frotmundi (De S. Fromundo seu Prodomundo Espisco) is the account of a Frankish nobleman named Fromond who traveled with his brothers to Jerusalem in the mid-9th century in order to expiate a crime. Fromond is the first known penitent to travel to the Holy Land for salvation. In Acta Sanctorum (Aa. Ss.) 58.

Bernard the Pilgrim. Bernard the Pilgrim (fl. 865), a Frankish monk.

Itinerarium of Bernard the Wise. An account of Bernard's travels to the Holy Land. In PPTS III.4.