Mystery flags: government issued or privately acquired?

In my collection, I have a couple of WWII Japanese “Good Luck” flags. Both have autographs and signatures in black ink Kanji characters, but one has red ovals red stamped Kanji characters inside the ovals. There are a few of the red ovals on the flag

A friend of mine called these “issue stamps.” I thought that these flags were personal items and not issued by the Japanese government.

I would be grateful if you or any of your experts could explain these red ovals and whether or not the flags were provided by the government to individual soldiers. — Martin Schoenfeld

Though he won’t allow us to refer to him as an “expert” (“The experts were our Fathers...”), we reached out to Gary Nila, author of several books on Japanese WWII militaria. Gary explained:

“The red seals originated in China and were used by the Chinese royalty to authenticate official documents and orders, their royal status, and were not introduced in Japan until approximately 60 AD.

“The “Chop,” a term from the Hindi word “Chapa,” stamp tools were originally made of stone, then made of ivory, bamboo, and in later years of rubber, to modern day plastics.

“In Japan, the Emperor would have been the first and only official seal in red ink, up until Japan’s feudal period (circa 750 AD), when some ranks of shoguns, warlords, and/or samurai would use the “Hanko” seal which translates to “red ink.” In the Hanko was Japanese kanji script that would identify the user.As time progressed in Japan, shrines, government entities, and persons of rank used the Hanko.By WWII, the Hanko was widely used as a personal signature by military officials, officers, government official, as well as temple shrines.Today’s Japan use the Hanko with everyday business life.

“This being discussed in brief, WWII personal prayer flags, farewell flags, were occasionally stamped with a Chop/Hanko in red ink from well wishers.These signed flags were not standard issue or official, but were presented to an individual (i.e. soldier) from their resident prefecture, employer prior to enlistment, military peers, spiritual monks from shrines, and on occasion by government officials; some of whom may have been in possession of a Chop/Hanko.”