Gusuku

In the Beginning, there was a gusuku; like the one called Toyomigusuku, which formed the basis for the modern-day city of Tomigusuku, south of Naha. The name of the castle came to designate the area around the castle and was later appropriated by the people who ruled the area (as with such storied figures as the Aji of Tomigusuku and the Wēkata of Tomigusuku) which acted just like the modern-day family name. In summary, the names spread in the following order of the castle → the district → the family name in Okinawa. The reason behind the surnames in Okinawa with the character 城 (shiro/castle): Ōshiro, Yamashiro, Hanashiro, Miyagi, Tamashiro, Yonashiro, Shiroma is their profound ties with the ancient stories of gusuku. 

What, then, is a gusuku? First, there are gusuku type A. Shuri Castle (to be precise the Shuri Gusuku), Nakijin Gusuku, Katsuren Gusuku, and Naka Gusuku fall into this category. They are large with sturdy ramparts. Then there is type B: gusuku built like warehouses or fortresses. Examples of this type are concentrated in the area around the Port of Naha. These sites include Omono Gusuku, where trade goods were stored; Iō Gusuku, where sulfur was kept; Yazaramori Gusuku and Mie Gusuku, where cannons were mounted to chase away enemy ships that might sneak into the port. 
　A and B do not account for all gusuku, though. On the main island of Okinawa there are over two hundred gusuku¹. With the two combined only make up about 20 to 30% of them. How, then, do we describe the others? Scholars still debate and dispute this question to this day and there are no clear answers or explanations. Some say they are the ruins of ancient communities, while others say they were sacred places of worship. Yet others argue that these smaller gusuku should still be regarded as castles. One alcohol-loving historian in the depths of his cups proposed that all gusuku began as communities with sacred places for worship, and some of those sacred places developed into type A, while the majority remained sacred places, and then some of those type A—like Shuri Gusuku, for example—were converted into type B. 

One thing is clear: Shuri Caslte has survived as a gusuku. By analyzing it, we can theorize and begin to understand other gusuku. I hope to live long enough to see how the dispute is settled.