Makuria was a kingdom located in what is today Northern Sudan and Southern Egypt. It was one of a group of Nubian kingdoms that emerged in the centuries after the fall of the Kushite Kingdom, which had dominated the region from approximately 800 BC to AD 350. Makuria originally covered the area along the Nile River from the Third Cataract to somewhere between the Fifth and Sixth Cataracts. It also had control over the trade routes, mines, and oases to the east and west. Its capital was Dongola, and the kingdom is sometimes known by the name of its capital. By the end of the 6th century it had converted to Christianity, but in the 7th century Egypt was conquered by the Islamic armies, and Nubia was cut off from the rest of Christendom. In 651 an Arab army invaded, but it was repulsed and a treaty known as the baqt was signed creating a relative peace between the two sides that lasted until the 13th century. Makuria expanded, annexing its northern neighbour Nobatia either at the time of the Arab invasion or during the reign of King Merkurios. The period from roughly 750 to 1150 saw the kingdom stable and prosperous, in what has been called the "Golden Age". Increased aggression from Egypt, and internal discord led to the state's collapse in the 14th century.