Most Japanese considers the "rising sun" flag part of their history. However, some in the two Koreas, China, Philippines and other Asian countries say the flag is a reminder of Japan’s wartime atrocities, and is comparable to the Nazi swastika.
That's why the flag has created anger at the Olympics, with some of the host nation's neighbors calling for it to be banned during the Tokyo Games.
There are two rising sun flags associated with Japan, whose very name in Japanese means "the sun's origin."
One is the country's national flag, called "nisshoki," or "hinomaru," which has a red disc on a white background. Few have a problem with this.
The other one also has a red disc, but it is surrounded by 16 rays that extend outward. Called "kyokujitsuki," this one has led to vehement protests from some of Japan's neighbors.
Both flags have been used for centuries. However, disputes about the "rising sun" flag date back to the early part of the 20th century. That is when Japan’s imperial navy used it as its official flag as the nation colonized the Korean Peninsula and invaded or occupied China and other Asian countries until its World War II defeat in 1945.
Japan's government emphasizes that both rising sun flags use the sun as a motif and were used across the country even before the wartime period. Even today, the rising sun with rays flag motif is used in everyday life in Japan, such as to celebrate a big catch by fishermen, childbirth and other festivities, the government says.
"An argument that it is a political statement or a symbol of militarism is completely irrelevant. I believe there is a big misunderstanding," now-Japanese Prime Minister Yoshihide Suga said in 2013, when he served as chief cabinet secretary.
Japan's neighbors view it differently.
In 2019, South Korea formally requested that the International Olympic Committee ban the flag at the Tokyo Olympics. Seoul said that the flag recalls the "scars and pain" of Asian people who experienced Japan’s wartime military aggression, similar to how the swastika "reminds Europeans of the nightmare of World War II."
North Korea’s state media, not known for understatement, have accused Japan of trying to turn "the flag of war criminals into a symbol of peace at the Olympics, saying that is "an intolerable insult to our people and other Asian people."