The Shoin-zukuri style was established for clarifying the social status orders of persons and for showing dignity of the person in authority in Azuchi-jo Castle built by Nobunaga or Osaka-jo Castle built by Hideyoshi TOYOTOMI.
信長の安土城や、豊臣秀吉の大坂城などにおいて身分の序列を著し権力者の威厳を示すため、書院造が完成した。