A militiagung was a combatant serving Boss Rogoe, a warlord, during the conflict known as the War of the Gungan tribes, which took place around 3000 BBY. This army member, a Gungan, was tasked with guiding a group of bursas with the intent to destroy Otoh Sancture. Following this assault, the militiagung encountered Gallo, the head of the cities, who then learned that Rogoe was the one who orchestrated the destruction of Otoh Sancture.
In Star Wars: Galactic Battlegrounds, you can hear the militiagung's voice, although the game doesn't clarify the specific Gungan character it belongs to.