The markets of Yamhad became a source of copper, which was imported from the mountains (probably Anatolian) and Cyprus. However, the Babylonian invasion of Mari had a negative impact on the trade between the two kingdoms, as the road became dangerous because of the loss of Mari's protection to the caravans. This led the Babylonian king Samsu-iluna to build many strongholds up the river valley, and to establish colonies of mercenaries known as the "Kassite Houses" to protect the middle Euphrates area. Those colonies later evolved into semi-independent polities that waged a war against the Babylonian king Ammi-Saduqa and caused the trade temporarily to stop. The people of Yamhad practiced the Amorite religion, and mainly worshiped the Northwest Semitic deities. The most important of these were Dagon, who was considered the father of the gods, and Hadad, who was the most important deity and the head of the pantheon. The kingdom was known as the "land of Hadad", who was famous as the Storm-God of Halab beginning in the middle of the 3rd millennium BC. His main temple was located on the citadel hill in the center of the city and remained in use from the 24th century BC, until at least the 9th century BC. The title "Beloved of Hadad" was one of the king's titles. Hadad was the kingdom's patron god, and all treaties were concluded in his name, which was also used to threaten other kingdoms, and to declare wars. As the Hurrian presence grew, so did Hurrian religious influences and some of the Hurrian deities found a place in the Yamhadite pantheon. King Abba-El I mentioned receiving the support of the Hurrian goddess Hebat in one of the Alalakh tablets (Hebat was the spouse of the Hurrian main deity Teshub, but in Abba-El I's tablet, she is associated with Hadad). Later, the Hurrians started to identify Teshub with Hadad, who became Teshub the Storm-God of Halab. Beside the general gods, the kings had a "head god", that is, a deity who had an intimate connection for the worshiper. King Yarim-Lim I described Hadad as the god of the state, but the Mesopotamian deity Sin as the god of his head. His son Hammurabi I did likewise.