The leader of the Roman Catholic Church, Pope Urban II, commissioned Peter to command an armed pilgrimage to Jerusalem. Before Peter went on his military expedition he received permission from Patriarch
Simeon II of Jerusalem. Peter was able to recruit from England, Lorraine, France, and Flanders.
Massacre of Jewish civilians In the spring of 1096 Peter was one of the prominent involved in the
Rhineland massacres against Jews. Peter and his troops participated in the torture and slaughter of Jews in
Lorraine,
Cologne,
Worms,
Speyer and
Mainz. Another group had been led by the knight count
Emicho of Leiningen who provoked the group to the massacres.
Hungary, Belgrade, Sofia Before reaching Constantinople, Peter and his followers began to experience difficulty. In
Zemun, the governor, who was a descendant of a Ghuzz Turk, and a colleague, were frightened by the army's size and decided to tighten regulations on a frontier. This would have been fine if a dispute about the sale of a pair of shoes had not occurred. This led to a riot and against Peter's wishes the town was attacked and the citadel was stormed. This resulted in 4,000 Hungarians being killed and many provisions being stolen. Then on 26 June 1096 Peter's army was able to cross the
Sava river. Then the army marched into
Belgrade, set the town on fire, and pillaged it. The army then made its way into and through Nish (
Niš) after an eight-day delay. After riding through Nish, the Crusaders made their way towards Sofia, when they were attacked on the road by Byzantine soldiers. The Crusaders took heavy losses, losing a quarter of their army. They arrived in
Sofia on 12 July nonetheless.
Constantinople Leading the first of the five sections of the People's Crusade to the destination of their pilgrimage, the Church of the Holy Sepulchre, he started (with 40,000 men and women) from Cologne in April 1096 and arrived (with 30,000 men and women) at Constantinople at the end of July. Byzantine emperor Alexios I Komnenos was less than pleased with their arrival, for along with the head of the Eastern Orthodox Church, Patriarch
Nicholas III of Constantinople, he was now required to provide for the care and sustenance of the vast host of paupers for the remainder of their journey. The forces then arrived in Constantinople on 1 August 1096. After a while, they arrived at a castle called
Xerigordon and captured it by taking possession of the castle's spring and well. After setting off to
Civetot, they set up camp near a village called Dracon. This is where the Turks ambushed Peter and his forces. This was the final battle of the People's Crusade that Peter led. Most of the paupers failed to make their way out of Catholic jurisdiction. The majority were incapable of being provided for by the various lordships and dioceses along the way and either starved, returned home or were put into servitude, while a substantial number were captured and sold into slavery by the various Slavic robber barons in the
Balkans, kindling the view of the Balkan Slavs as unredeemed robbers and villains. Peter gathered the only other section which had succeeded in reaching Constantinople, that of
Walter Sans Avoir, into a single group and encamped the still numerous pilgrims around Constantinople while he negotiated transport of the People's Crusade to the
Holy Land. The Emperor meanwhile had failed to provide for the pilgrims adequately and the camp made itself a growing nuisance, as the increasingly hungry paupers turned to pilfering imperial stores. Alexios, worried at the growing disorder and fearful of his standing before the coming armed Crusader armies, quickly concluded negotiations and shipped them across the
Bosporus to the Asiatic shore at the beginning of August, with promises of guards and passage through the Turkish lines. He warned the People's Crusade to await his orders, but in spite of his warnings, the paupers entered Turkish territory. The Turks began skirmishing with the largely unarmed host. Peter returned in desperation to Constantinople, seeking the Emperor's help. In Peter's absence, the pilgrims were ambushed and cut to pieces in detail by the Turks, who were more disciplined, at the
Battle of Civetot. Despite Peter's pronunciations of divine protection, the vast majority of the pilgrims were slaughtered by the swords and arrows of the Turks or were enslaved. Left in Constantinople with the small number of surviving followers, during the winter of 1096–1097, with little hope of securing Byzantine support, the People's Crusade awaited the coming of the armed crusaders as their sole source of protection to complete the pilgrimage.
To Jerusalem When the princes arrived, Peter joined their ranks as a member of the council in May 1097, and with the little following which remained they marched together through
Asia Minor to
Jerusalem. While his "paupers" never regained the numbers prior to the
Battle of Civetot, his ranks were increasingly replenished with disarmed, injured, or bankrupted crusaders. Nonetheless, aside from a few rousing speeches to motivate the Crusaders, he played a subordinate part in the remaining history of the First Crusade which at this point clearly settled on a military campaign as the means to secure the pilgrimage routes and holy sites in
Palestine. Peter appears, at the beginning of 1098, as attempting to escape from the privations of the
siege of Antioch—showing himself, as
Guibert of Nogent says, a "fallen star." Guibert and other sources go on to write that Peter was responsible for the speech before the half-starved and dead Crusaders which motivated their sally from the gates of Antioch and their subsequent victory over the overwhelmingly superior Muslim army besieging the city. Thus, having recovered his stature, in the middle of the year he was sent by the princes to invite
Kerbogha to settle all differences via a duel, which the emir subsequently declined. In 1099 Peter appears as the treasurer of the alms at the
siege of Arqa, and as leader of the supplicatory processions around the walls of Jerusalem
before it fell, and later within Jerusalem which preceded the Crusaders' surprising victory at the
Battle of Ascalon (August). At the end of 1099, Peter went to
Latakia, and sailed thence for the West. From this time he disappears from the historical record.
Albert of Aix records that he died in 1131, as prior of a church of the Holy Sepulchre which he had founded in France. ==Role in preaching the First Crusade==