zones became . Later, in 1871, the government designated Tokyo, Osaka, and Kyoto as fu, and relegated the other fu to the status of ken. During World War II, in 1943, Tokyo became a to, a new type of pseudo-prefecture. Despite the differences in terminology, there is little functional difference between the four types of local governments. The subnational governments are sometimes collectively referred to as in Japanese, which is a combination of the four terms. To Tokyo is referred to as , which is often translated as "metropolis". The Japanese government translates as "Tokyo Metropolis" in almost all cases, and the government is officially called the "Tokyo Metropolitan Government". Following the capitulation of shogunate Edo in 1868, Tōkyō-fu (an urban prefecture like Kyoto and Osaka) was set up and encompassed the former city area of Edo under the Fuhanken sanchisei. After the abolition of the han system in the first wave of prefectural mergers in 1871/72, several surrounding areas (parts of Urawa, Kosuge, Shinagawa and Hikone prefectures) were merged into Tokyo, and under the system of (numbered) "large districts and small districts" (daiku-shōku), it was subdivided into eleven large districts further subdivided into 103 small districts, six of the large districts (97 small districts) covered the former city area of Edo. When the ancient ritsuryō districts were reactivated as administrative units in 1878, Tokyo was subdivided into 15 [urban] districts (-ku) and initially six [rural] districts (-gun; nine after the Tama transfer from Kanagawa in 1893, eight after the merger of East Tama and South Toshima into Toyotama in 1896). Both urban and rural districts, like everywhere in the country, were further subdivided into urban units/towns/neighbourhoods (-chō/-machi) and rural units/villages (-mura/-son). The yet unincorporated communities on the Izu (previously part of Shizuoka) and Ogasawara (previously directly Home Ministry-administrated) island groups became also part of Tokyo in the 19th century. When the modern municipalities – [district-independent] cities and [rural] districts containing towns and villages – were introduced under the Yamagata-Mosse laws on local government and the simultaneous Great Meiji merger was performed in 1889, the 15 -ku became wards of Tokyo City, initially Tokyo's only independent city (-shi), the six rural districts of Tokyo were consolidated in 85 towns and villages. In 1893, the three Tama districts and their 91 towns and villages became part of Tokyo. As Tokyo city's suburbs grew rapidly in the early 20th century, many towns