The highest religious and political offices in Jerusalem were usually held by Europeans who had arrived on pilgrimage or crusade.
William was one of the few natives with a European education, and he quickly rose through the ranks.
After his return to the Holy Land in 1165, he became canon of the cathedral at Acre.
In 1167 he was appointed archdeacon of the cathedral of Tyre by Frederick de la Roche, archbishop of Tyre, with the support of King Amalric.

Amalric had come to power in 1164 and had made it his goal to conquer Egypt.
Egypt had been invaded by King Baldwin I fifty years earlier, and the weak Fatimid Caliphate was forced to pay yearly tribute to Jerusalem.
Amalric turned towards Egypt because Muslim territory to the east of Jerusalem had fallen under the control of the powerful Zengid sultan Nur ad-Din.
Nur ad-Din had taken control of Damascus in 1154, six years after the disastrous siege of Damascus by the Second Crusade in 1148.
Jerusalem could now expand only to the southwest, towards Egypt, and in 1153 Ascalon, the last Fatimid outpost in Palestine, fell to the crusaders.
Nur ad-Din, however, also wished to acquire Egypt, and sent his army to hinder Amalric's plans.
This was the situation in the east when William returned from Europe.
In 1167 Amalric married Maria Comnena, grand-niece of Byzantine emperor Manuel I Comnenus, and in 1168 the king sent William to finalize a treaty for a joint Byzantine-crusader campaign against Egypt.
The expedition, Amalric's fourth, was the first with support from the Byzantine navy.
Amalric, however, did not wait for the fleet to arrive.
He managed to capture Damietta, but within a few years he was expelled from Egypt by one of Nur ad-Din's generals, Saladin, who would later become Jerusalem's greatest threat.

Meanwhile, William continued his advancement in the kingdom.
In 1169 he visited Rome, possibly to answer accusations made against him by Archbishop Frederick, although if so, the charge is unknown.
It is also possible that while Frederick was away on a diplomatic mission in Europe, a problem within the diocese forced William to seek the archbishop's assistance.

 On his return from Rome in 1170 he may have been commissioned by Amalric to write a history of the kingdom.
He also became the tutor of Amalric's son and heir, Baldwin IV.
When Baldwin was thirteen years old, he was playing with some children, who were trying to cause each other pain by scratching each other's arms. "
The other boys gave evidence of pain by their outcries," wrote William, "but Baldwin, although his comrades did not spare him, endured it altogether too patiently, as if he felt nothing  ...  It is impossible to refrain from tears while speaking of this great misfortune."
William inspected Baldwin's arms and recognized the possible symptoms of leprosy, which was confirmed as Baldwin grew older.

Amalric died in 1174, and Baldwin IV succeeded him as king.
Nur ad-Din also died in 1174, and his general Saladin spent the rest of the decade consolidating his hold on both Egypt and Nur ad-Din's possessions in Syria, which allowed him to completely encircle Jerusalem.
The subsequent events have often been interpreted as a struggle between two opposing factions, a "court party" and a "noble party."
The "court party" was led by Baldwin's mother, Amalric's first wife Agnes of Courtenay, and her immediate family, as well as recent arrivals from Europe who were inexperienced in the affairs of the kingdom and were in favour of war with Saladin.
The "noble party" was led by Raymond III of Tripoli and the native nobility of the kingdom, who favoured peaceful co-existence with the Muslims.
This is the interpretation offered by William himself in the Historia, and it was taken as fact by later historians.
Peter W. Edbury, however, has more recently argued that William must be considered extremely partisan as he was naturally allied with Raymond, who was responsible for his later advancement in political and religious offices.
The accounts of the 13th-century authors who continued the Historia in French must also be
The highest religious and political offices in Jerusalem were usually held by Europeans who had arrived on pilgrimage or crusade. William was one of the few natives with a European education, and he quickly rose through the ranks. After his return to the Holy Land in 1165, he became canon of the cathedral at Acre. In 1167 he was appointed archdeacon of the cathedral of Tyre by Frederick de la Roche, archbishop of Tyre, with the support of King Amalric.
Amalric had come to power in 1164 and had made it his goal to conquer Egypt. Egypt had been invaded by King Baldwin I fifty years earlier, and the weak Fatimid Caliphate was forced to pay yearly tribute to Jerusalem. Amalric turned towards Egypt because Muslim territory to the east of Jerusalem had fallen under the control of the powerful Zengid sultan Nur ad-Din. Nur ad-Din had taken control of Damascus in 1154, six years after the disastrous siege of Damascus by the Second Crusade in 1148. Jerusalem could now expand only to the southwest, towards Egypt, and in 1153 Ascalon, the last Fatimid outpost in Palestine, fell to the crusaders. Nur ad-Din, however, also wished to acquire Egypt, and sent his army to hinder Amalric's plans. This was the situation in the east when William returned from Europe. In 1167 Amalric married Maria Comnena, grand-niece of Byzantine emperor Manuel I Comnenus, and in 1168 the king sent William to finalize a treaty for a joint Byzantine-crusader campaign against Egypt. The expedition, Amalric's fourth, was the first with support from the Byzantine navy. Amalric, however, did not wait for the fleet to arrive. He managed to capture Damietta, but within a few years he was expelled from Egypt by one of Nur ad-Din's generals, Saladin, who would later become Jerusalem's greatest threat.
Meanwhile, William continued his advancement in the kingdom. In 1169 he visited Rome, possibly to answer accusations made against him by Archbishop Frederick, although if so, the charge is unknown. It is also possible that while Frederick was away on a diplomatic mission in Europe, a problem within the diocese forced William to seek the archbishop's assistance.
 On his return from Rome in 1170 he may have been commissioned by Amalric to write a history of the kingdom. He also became the tutor of Amalric's son and heir, Baldwin IV. When Baldwin was thirteen years old, he was playing with some children, who were trying to cause each other pain by scratching each other's arms. "The other boys gave evidence of pain by their outcries," wrote William, "but Baldwin, although his comrades did not spare him, endured it altogether too patiently, as if he felt nothing  ...  It is impossible to refrain from tears while speaking of this great misfortune." William inspected Baldwin's arms and recognized the possible symptoms of leprosy, which was confirmed as Baldwin grew older.
Amalric died in 1174, and Baldwin IV succeeded him as king. Nur ad-Din also died in 1174, and his general Saladin spent the rest of the decade consolidating his hold on both Egypt and Nur ad-Din's possessions in Syria, which allowed him to completely encircle Jerusalem. The subsequent events have often been interpreted as a struggle between two opposing factions, a "court party" and a "noble party." The "court party" was led by Baldwin's mother, Amalric's first wife Agnes of Courtenay, and her immediate family, as well as recent arrivals from Europe who were inexperienced in the affairs of the kingdom and were in favour of war with Saladin. The "noble party" was led by Raymond III of Tripoli and the native nobility of the kingdom, who favoured peaceful co-existence with the Muslims. This is the interpretation offered by William himself in the Historia, and it was taken as fact by later historians. Peter W. Edbury, however, has more recently argued that William must be considered extremely partisan as he was naturally allied with Raymond, who was responsible for his later advancement in political and religious offices. The accounts of the 13th-century authors who continued the Historia in French must also be 
William of Tyre