Gokishichidō

thumb|upright=2|Regions in the 8th century (see below for modern Japanese prefectures) was the name for ancient administrative units organized in Japan during the Asuka period (AD 538–710), as part of a legal and governmental system borrowed from the Chinese. Though these units did not survive as administrative structures beyond the Muromachi period (1336–1573), they did remain important geographical entities until the 19th century. The Gokishichidō consisted of five provinces in the Kinai () or capital region, plus seven dō () or circuits, each of which contained provinces of its own.

When Hokkaido was included as a circuit after the defeat of the Republic of Ezo in 1869, the system was briefly called . The abolition of the han system abolished the -han (early modern feudal domains) in 1871, -dō/circuits and provinces were per se not abolished by the abolition of domains; but the prefectures that sprang from the domains became the primary administrative division of the country and were soon merged and reorganized to territorially resemble provinces in many places. "Hokkai circuit" (Hokkai-dō) was the only -dō that would survive as administrative division, but it was later increasingly treated as "Hokkai prefecture" (Hokkai-dō); finally after WWII, the -dō was fully regarded as a prefecture: from 1946, the prefectures (until then only -fu/-ken) were legally referred to as -dō/-fu/-ken, from 1947 as -to/-dō/-fu/-ken.