The government released a list Tuesday of over 230,000 Korean victims during the Japanese colonial occupation of the peninsula (1910-45), the first publication of such a list.
It includes people killed during Korea's first independence movement uprising on March 1, 1919, and also during the Great Kanto Earthquake which occurred in Japan in 1923.
Historians have estimated that around 140,000 Koreans were killed by the Japanese when the earthquake took place because of a false rumor that discontented Koreans were attempting to overthrow the government.
Also included were those coerced into working for Japanese companies during World War II. According to the National Archives of Korea (NAK), the list was compiled after careful analysis of data from 1953 discovered by accident at the Korean Embassy in Tokyo in June.
"The list must have been made after President Rhee Syngman ordered a nationwide investigation into the victims of the colonial era in 1952 before holding a Seoul-Tokyo meeting in 1953," said the NAK in a briefing.
Experts say the new information is likely to help Seoul push Tokyo to come to the negotiation table for further discussions regarding compensation.
Tokyo argues that the compensation issue was settled under the 1965 Korea-Japan Claims Settlement Agreement which exempted Tokyo from any responsibility regarding damage incurred during its colonial rule of the Korean Peninsula. In exchange, Seoul received $800 million in grants and soft loans.
The treaty has long been the basis for Japan's refusal to compensate Korean victims.
Earlier this month, during high-ranking bilateral economic talks held in Tokyo, Korean officials again called for compensation but the Japanese officials once again rejected the call, citing that "All matters have been resolved through the 1965 claims settlement agreement."
"The list disclosed this time is an official one and is also a detailed record, encompassing not only the names of the casualties but also their home addresses and dates of birth," said NAK President Bahk Gyung-goog. "This will serve as a solid basis when requesting proper compensation from Japan."
High-ranking Japanese officials and politicians under the hawkish Shinzo Abe administration have been making inflammatory remarks about the issue, even denying its wrongdoings of the past.
This continues to put a strain on Tokyo's ties with its neighbors and Korea and China continue to call for an official apology and compensation from the Japanese government.