Joy Bangla is a slogan and war cry used in Bangladesh and Indian state of West Bengal to indicate nationalism towards the geopolitical, cultural and historical region of Bengal and Bangamata. It is also recognised as the national slogan of Bangladesh. It translates roughly to "Victory to Bengal" or "Hail Bengal".

A battle cry or war cry is a yell or chant taken up in battle, usually by members of the same combatant group. Battle cries are not necessarily articulate, although they often aim to invoke patriotic or religious sentiment. Their purpose is a combination of arousing aggression and esprit de corps on one's own side and causing intimidation on the hostile side. Battle cries are a universal form of display behaviour aiming at competitive advantage, ideally by overstating one's own aggressive potential to a point where the enemy prefers to avoid confrontation altogether and opts to flee. In order to overstate one's potential for aggression, battle cries need to be as loud as possible, and have historically often been amplified by acoustic devices such as horns, drums, conches, carnyxes, bagpipes, bugles, etc..