At home Adad-nirari conducted a vigorous policy. He developed the resources of the city state of Asshur by constructing a great dam and quay wall, while he contributed to the prosperity of the priesthood and the growth of Assyrian culture by extending the temple of the god Ashur. Ere he died, he assumed the proud title of "Shar Kishshate", "king of the world", which was also used by his son Shalmaneser I. His reign extended over a period of thirty years and terminated about 1300 B.C.
Soon after Shalmaneser came to the throne his country suffered greatly from an earthquake, which threw down Ishtar's temple at Nineveh and Ashur's temple at Asshur. Fire broke out in the latter building and destroyed it completely.
These disasters did not dismay the young monarch. Indeed, they appear to have stimulated him to set out on a career of conquest, to secure treasure and slaves, so as to carry out the work of reconstructing the temples without delay. He became as great a builder, and as tireless a campaigner as Thothmes III of Egypt, and under his guidance Assyria became the most powerful nation in Western Asia. Ere he died his armies were so greatly dreaded that the Egyptians and Assyrians drew their long struggle for supremacy in Syria to a close, and formed an alliance for mutual protection against their common enemy.
It is necessary at this point to review briefly the history of Palestine and north Syria after the period of Hittite expansion under King Subbi-luliuma and the decline of Egyptian power under Akhenaton. The western part of Mitanni and the most of northern Syria had been colonized by the Hittites.[[410]] Farther south, their allies, the Amorites, formed a buffer State on the borders of Egypt's limited sphere of influence in southern Palestine, and of Babylonia's sphere in southern Mesopotamia. Mitanni was governed by a subject king who was expected to prevent the acquisition by Assyria of territory in the north-west.
Subbi-luliuma was succeeded on the Hittite throne by his son, King Mursil, who was known to the Egyptians as "Meraser", or "Maurasar". The greater part of this monarch's reign appears to have been peaceful and prosperous. His allies protected his frontiers, and he was able to devote himself to the work of consolidating his empire in Asia Minor and North Syria. He erected a great palace at Boghaz Köi, and appears to have had dreams of imitating the splendours of the royal Courts of Egypt, Assyria, and Babylon.
At this period the Hittite Empire was approaching the zenith of its power. It controlled the caravan roads of Babylonia and Egypt, and its rulers appear not only to have had intimate diplomatic relations with both these countries, but even to have concerned themselves regarding their internal affairs. When Rameses I came to the Egyptian throne, at the beginning of the Nineteenth Dynasty, he sealed an agreement with the Hittites, and at a later date the Hittite ambassador at Babylon, who represented Hattusil II, the second son of King Mursil, actually intervened in a dispute regarding the selection of a successor to the throne.
The closing years of King Mursil's reign were disturbed by the military conquests of Egypt, which had renewed its strength under Rameses I. Seti I, the son of Rameses I, and the third Pharaoh of the powerful Nineteenth Dynasty, took advantage of the inactivity of the Hittite ruler by invading southern Syria. He had first to grapple with the Amorites, whom he successfully defeated. Then he pressed northward as far as Tunip, and won a decisive victory over a Hittite army, which secured to Egypt for a period the control of Palestine as far north as Phoenicia.
When Mursil died he was succeeded on the Hittite throne by his son Mutallu, whom the Egyptians referred to as "Metella" or "Mautinel". He was a vigorous and aggressive monarch, and appears to have lost no time in compelling the Amorites to throw off their allegiance to Egypt and recognize him as their overlord. As a result, when Rameses II ascended the Egyptian throne he had to undertake the task of winning back the Asiatic possessions of his father.
The preliminary operations conducted by Rameses on the Palestinian coast were attended with much success. Then, in his fifth year, he marched northward with a great army, with purpose, it would appear, to emulate the achievements of Thothmes III and win fame as a mighty conqueror. But he underestimated the strength of his rival and narrowly escaped disaster. Advancing impetuously, with but two of his four divisions, he suddenly found himself surrounded by the army of the wily Hittite, King Mutallu, in the vicinity of the city of Kadesh, on the Orontes. His first division remained intact, but his second was put to flight by an intervening force of the enemy. From this perilous position Rameses extricated himself by leading a daring charge against the Hittite lines on the river bank, which proved successful. Thrown into confusion, his enemies sought refuge in the city, but the Pharaoh refrained from attacking them there.
Although Rameses boasted on his return home of having achieved a great victory, there is nothing more certain than that this campaign proved a dismal failure. He was unable to win back for Egypt the northern territories which had acknowledged the suzerainty of Egypt during the Eighteenth Dynasty. Subsequently he was kept fully engaged in maintaining his prestige in northern Palestine and the vicinity of Phoenicia. Then his Asiatic military operations, which extended altogether over a period of about twenty years, were brought to a close in a dramatic and unexpected manner. The Hittite king Mutallu had died in battle, or by the hand of an assassin, and was succeeded by his brother Hattusil II (Khetasar), who sealed a treaty of peace with the great Rameses.