Can anything be told from this WW2 Japanese Flag?

by Razor488

Hello,

My Grandfather was an Army veteran in the pacific theatre of WW2. I recently discovered this Japanese flag that belonged to him, but I don’t know anything about it. He fought on Iwo Jima, Saipan, Karigador, and Peleliu. My grandfather passed away in 2011.

Can anything be told from this flag and the writings that are on it?

https://goo.gl/photos/xie7AK4zHuk3zCo9A

Thank you!

ParkSungJun

This flag apparently belonged to a Commander Ooi of the Imperial Japanese Navy. Unfortunately I cannot quite read the last character of the name due to the angle/my poor Japanese.

The big text on the top of the flag in the picture is simply a wish for good luck in battle. The numerous small text on the bottom of the picture on the right are presumably signatures and well wishes much like signing a yearbook.