Also known as the Third Wizarding War, the Dark War was the conflict between the Ministry of Magic and theAurors against the Oracles and their allies. This major conflict had roots long before the First and Second Wizarding War, as some stretched back to the Middle Ages, but the war began officially in March 2001 and stopped in January 2002 after a long manhunt for Malory and his accomplices after one of his own, Edward Vearin, betrayed him and fed information to the Ministry.
The organization known as the Oracle was led by Carthus Malory, and consisted of several Dark Witches and Wizards, and their goal was to spark a war between the Muggle and Wizard government so they could usurp power from their weakened states after the war. In opposition though, the Ministry of Magic, and the Aurors plus several magical citizens who opposed the Oracle’s view including Harry Potter, Hermione Granger, Ron Weasley, and Neville Longbottom.