The reform was based on the "Laws on the City Formation" () of the Republic of China. This law was passed in the early 20th century. The criteria for being a provincial city included being the provincial capital as well as having a population of over 200,000, or over 100,000 if the city had particular significance in politics, economics, and culture. The division reform in 1945 had some compromises between the Japanese and the Chinese systems, some of the cities with population under the criteria were still be established as provincial cities.