It was established in February 1911 as part of the Japanese central government's Imperial Household Ministry but was under the day-to-day supervision of the Government-General of Korea.
This included the imperial household, property, rituals, and institutions such as the museum, zoo and gardens set up at Changgyeonggung Palace.
However, unlike the situation before 1910 where the Korean emperor could make decisions regarding the budget and staffing, the ex-emperor had no such power over Yiwangjik, a department of the Imperial Household Ministry.
Yi-wang or Ri-o (李王), literally "King Yi", is the title devised for the ex-Emperor of Korea within the Kazoku system.
There was no systematic preservation of the imperial family's movable property (furniture, pottery etc) after WWII, and they became scattered amongst the Yiwangjik descendant organisations and palace storerooms.