The flag, depicting a red sun with 16 rays extending outward, has been used by Japan for centuries and is still used by its military. It was also used by the Japanese army and navy during World War II and is resented by many South Koreans because of Japan’s brutal colonial rule of the Korean Peninsula from 1910 to 1945.
It is distinct from Japan’s national flag, a simple crimson disk on a white background, which the country’s Olympic team will carry.
Relations between South Korea and Japan have plummeted this year to their lowest level in decades. The dispute began over compensation for forced labor during colonial rule and spiraled into tit-for-tat moves undermining trade and security cooperation.
Many South Koreans are boycotting Japanese goods, from beer to clothes, and tourism between the two countries has slumped.
Last month, South Korean Olympic officials urged the Tokyo Organizing Committee to ban any use of the Rising Sun flag at the Games, a request denied by the Japanese side. “It is widely used in Japan; the flag itself is not considered to be a political statement, so it is not viewed as a prohibited item,” the Tokyo Organizing Committee said.
In its letter to the IOC, written in English, the South Korean government described the Rising Sun as “a war flag of Japanese army associated with Japanese imperialism during Japan’s military aggression in Asia including the Pacific War since the end of 19th century.”
It also pointed out that Japanese far-right groups use the flag for demonstrations against foreigners.
The flag reminds many Asians, including Koreans and the Chinese, of “historical wounds and pains,” the South Korean letter said. It compared the flag to Nazi Germany’s swastika.
The South Korean ministry said displays of the Rising Sun flag would not correspond to “Olympism and the Olympic Value for promoting a peaceful society and the harmonious development of humankind,” and it asked the IOC to make the Tokyo Organizing Committee prohibit the banner’s use in Olympic venues.
South Korean outrage over the use of the Rising Sun flag is a relatively recent phenomenon, largely dating to a soccer match between the two nations in 2011. It has been inflamed by anti-Japan nationalism and the sentiment that Japan has not properly apologized for its behavior during colonial rule.
Last week, Japan pulled out of an international fleet review hosted by South Korea after refusing to accede to a demand not to fly the Rising Sun flag from its ships.
Min Joo Kim in Seoul and Akiko Kashiwagi in Tokyo contributed to this report.