The origin of the name "Swahili" comes from the Arabic word sahil or coast. To summarize the meaning of "Swahili", it literally means "the people of the coast". Modern Kiswalili is Bantu with a few Arabic words. These words came from the Arabs who moved to the area and settled with the locals. With the help of writing by the Arabs, Kiswahili became a written language. After some time, "Swahili" came to be known as Islamic in religion, but African in language and people. As more and more Muslims immigrated to the East Coast, their influence increased. They married into the ruling families and mosques were built as a result. Further north, rectangular houses were being built and it is assumed that trade was growing with Egypt and the Mediterranean. The island of Kilwa, under Shirazi rule, found a way to control the gold trade. Mogadishu was in control and, using Muslim contacts, they organized the transport of gold dust from the "Land of Sofala" to markets in the north. Kilwa merchants sent ships to Sofala and established settlements. Purchasing directly from interior Africans, Kilwa took over the southern gold trade from Mogadishu 1200