Documents and letters from the Righteous Armies, who led the resistance against the Japanese invasion at the end of the Joseon Dynasty, returned to South Korea in time for Liberation Day.

On Wednesday, the Korea Heritage Service and the Overseas Cultural Heritage Foundation unveiled the "Documents Related to Righteous Armies" and the "Sourcebook on Korea-Japan Relations" at the National Palace Museum of Korea.

Among the documents is the "Thirteen Provinces Alliance of Righteous Armies," a collection detailing anti-Japanese forces from all provinces of Korea, written between 1851 and 1909.

The collection also includes writings by high-ranking Righteous Army officials Heo Wi and Yi Gang-nyeon, as well as letters by scholar Choe Ik-hyeon.

The thirteen documents are mounted in two handscrolls, with notes in the main text which indicate that a Japanese military policeman named Gaecheon Jangchi collected and organized them into their current format in 1939.