The Battle of Brazil was a three day campaign during the First Battle of Earth. The Covenant intercepted a message stating that the UNSC was building a new ONI base to breed new SPARTAN-IIIs at Brazil in South America at the Southeast Region. Fearing that more SPARTAN-IIIs could jeperdize the Great Journey, Regret ordered small group of Covenant forces to attack Brazil and glass the whole region. Three days of brutal fighting, the UNSC prevailed and Truth orderd and the remaining forces retreat and return to Mombasa. The ONI construction was postponed right after the battle.