At the beginning of Indonesia's independence, the former Riau Residency area was merged and incorporated in the Sumatra Province based in Bukittinggi. Along with the crackdown on PRRI sympathizers, Central Sumatra was further divided into three provinces, namely North Sumatra, Central Sumatra, and South Sumatra. At that time, Central Sumatra became the strongest base of the PRRI, this situation caused the central government to develop a strategy to break Central Sumatra in order to weaken the PRRI movement. Subsequently, in 1957, based on Emergency Law Number 19 of 1957, Central Sumatra was divided into three provinces, namely Riau, Jambi and West Sumatra. Then what became the newly formed Riau province is the former Siak Sri Sultanate area of Inderapura and Riau Residency as well as the Kampar which was previously occupied during the occupation of the Japanese army in the "Rhio Shu" area.