Top text is read right to left as 朝鮮歩兵第七十五聯隊 "Korea Infantry, 75th Regiment". Right text is read vertically right to left 除隊紀念 "discharge commemoration" this is standard honorable discharge terminology. Left text could be a name for a location in Korea, alternatively it could be read as 上等兵 "superior private" a rank in the Imperial Japanese Army. The Korea 75th Infantry Regiment was created in the 1910s after Japan took control of the peninsula. It was part of the 19th Division which was created to defend Japan's northern border in Korea. The base mark is likely the makers mark for a kiln that has been lost to time.