Salah al-Din Yusuf bin Ayub or Saladin as he is more commonly known was born in 1138 AD The meaning of his Arabic name is "justice of faith". As a child, Saladin was a studious boy who studied the Quran and poetry. It was known that he loved studying the Quran and other literature more than joining and fighting in the army. At the age of fourteen he entered the military service of his uncle Nur ed-Din, another great and respected Arab warrior. Another teacher of the young Saladin was the Saracen leader Zenghi who in 1144 overthrew the city of Edessa, which for many years had been an outpost of the Western world due to its proximity to Antioch. Saladin learned his military lessons well and began to distinguish himself among Nur ed-Din's forces. In 1169 AD Saladin served with another uncle named Shirkuh as second to the commander-in-chief of the Syrian army. Shirkuh died just two months after Saladin received his new position. As the leader of a foreign army from Syria, he had no control even over the Shiite Egyptian army, which was led in the name of the weak and powerless Caliph (Muslim religious leader or Muslim Pope) Al-Adid. When the caliph died in September 1171, Saladin had the imams pronounce the name of Al-Mustadi, the Abbasid caliph in Baghdad, in the sermon before Friday prayers instead of Al-Adid. The people liked the decision and Al-Adid's name was forgotten. Saladin took control of Egypt, being the natural choice as the region's caliph had died and as the people needed a new leader. Now Saladin ruled Egypt, but officially representing Nur ad-Din, its old lord who also recognized the Abbasid caliph. Saladin revitalized Egypt's economy, reorganized its military forces, and, following his father's advice, stayed away from any conflict with Nur ad-Din, its formal overlord, after becoming sultan of Egypt. He waited until Nur ad-Din's death before conjuring a forced military uprising of militias for power in smaller Muslim states such as Damascus, Syria, Alleppo, Mawsil, and Iraq, and taking them under his control. While Saladin was building his power, he generally avoided any conflict with the Crusader kingdom, although every time he fought them, he defeated them. An exception was the Battle of Montgisard in November 25, 1177.