noun
ancient nation; former country
Refers to a nation that existed in the past, often in historical or geographical contexts.
この地域にはかつて旧国が栄えていた。
An ancient nation once flourished in this region.
noun
homeland; native land; birthplace
Used for one's country of origin or the place where one was born, often with a nostalgic or formal tone.
彼は旧国を離れて長い年月が経った。
Many years have passed since he left his homeland.