Dei gesta per Francos ("Deeds of God through the Franks") is a narrative of the First Crusade by Guibert of Nogent written between 1107 and 1108.
 Traditionally it has not been well received by scholars, but recent translators and editors (such as Levine 1997 and Rubenstein 2002) have shown it to contain important original material.
Warner of Grez (also Werner or Garnier of Grey or Gray) (died July 23, 1100) Count of Grez, was a French nobleman from Grez-Doiceau, currently in Walloon Brabant in Belgium.
 He was one of the participants in the army of Godfrey of Bouillon of the First Crusade, and died in Jerusalem a year after the crusade ended.
 His brother Henry is also listed as a Count of Grez and accompanied Warner on the First Crusade.
Ekkehard of Aura (Latin: "Ekkehardus Uraugiensis" ; died 1126) was the Abbot of Aura (a monastery founded by Otto, Bishop of Bamberg, on the Franconian Saale river, near Bad Kissingen, Bavaria) from 1108.
 A Benedictine monk and chronicler, he made updates to the "World Chronicle" ("Chronicon universale") of Frutolf of Michelsberg adding important German history between 1098 and 1125 during the reign of Emperor Henry V, in which he sided strongly with the papacy in the Investiture Controversy.
 He was a participant in the Crusade of 1101 (Lerner, 1989), and provided important source material for the Rhineland massacres of Jews and for the First Crusade.
Ralph the Red (Ralph le Roux, Raoul II Rufus) of Pont-Echnfrey (1070-25 November 1120), son of either Guillaume de Pont-Echanfrey or his brother Raoul I. Ralph was a knight who first served Robert Guiscard and then participated both in the First Crusade and in the Crusade of Robert’s son Bohemond of Antioch-Taranto as part of his first army.
 A semi-professional soldier loyal to the family of Guiscard, he accompanying Bohemond to Apulia in 1107 and then Antioch in 1108.
 Ralph’s brother Guascelin (d. 1109 or after) also accompanied Bohemond.
 In 1119, he had joined the forces of Henry I of England in his campaign against Louis VI of France, and helped Henry's son Richard evade capture by the French at Les Andelys.
The Armies of Bohemond of Taranto include a major component of the First Crusade under the leader Bohemond I of Antioch formed in 1097.
 He is regarded as the real leader of the First Crusade.
 He formed a second army in 1107 to defend Antioch but instead used it to attack the Byzantine emperor Alexios I Komnenos, resulting in the Treaty of Devol, codifying Bohemond’s defeat.
 Runciman estimates that the first army included 500 cavalry and 3500 infantrymen (plus clergy and non-combatants) and other estimates that the second army was at 34,000 personnel strength are likely greatly exaggerated.
The Treaty of Devol (Greek: συνθήκη της Δεαβόλεως ) was an agreement made in 1108 between Bohemond I of Antioch and Byzantine Emperor Alexios I Komnenos, in the wake of the First Crusade.
 It is named after the Byzantine fortress of Devol (in modern Albania).
 Although the treaty was not immediately enforced, it was intended to make the Principality of Antioch a vassal state of the Byzantine Empire.
The Crusade of 1101 was a minor crusade of three separate movements, organized in 1100 and 1101 in the successful aftermath of the First Crusade.
 It is also called the Crusade of the Faint-Hearted due to the number of participants who joined this crusade after having turned back from the First Crusade.
Richard of Salerno ( 1060 – 1114), who is not to be confused with his homonym cousin Richard of Hauteville, was a participant in the First Crusade and regent of the County of Edessa from 1104 to 1108.
Bohemond II (1107/1108 – February 1130) was Prince of Taranto from 1111 to 1128 and Prince of Antioch from 1111/1119 to 1130.
 He was the son of Bohemond I, who in 1108 was forced to submit to the authority of the Byzantine Empire in the Treaty of Devol.
 Three years later, the infant Bohemond inherited the Principality of Taranto under the guardianship of his mother, Constance of France.
 The Principality of Antioch was administered by his father's nephew, Tancred, until 1111.
 Tancred's cousin, Roger of Salerno, managed the principality from 1111 to 1119.
 After Roger died in the Battle of the Field of Blood, Baldwin II of Jerusalem took over the administration of Antioch.
 However, he did acknowledge Bohemond's right to personally rule the principality upon reaching the age of majority.
Gervaise of Bazoches (died May 1108), Prince of Galilee and Lord of Tiberias, was a crusader on the First Crusade.

Question: The Treaty of Devol made in 1108 codified what leader's defeat in the First Crusade?
Answer: Bohemond I of Antioch