The Mandalore takeover, also referenced as the Mandalore conquest, or the Mandalore assault, transpired during the Clone Wars. It involved the Mandalorian splinter group Death Watch and rogue Sith Lords Maul alongside his sibling Savage Opress. They orchestrated a deceptive seizure of the Mandalorian homeworld, deposing the pacifistic New Mandalorian administration led by Duchess Satine Kryze. The scheme originated from an alliance between Death Watch and the Sith brothers, Maul and Savage Opress. Death Watch had long been attempting to seize control of the Mandalore government, while Maul aimed to establish a power base. Both sought vengeance against Jedi Master Obi-Wan Kenobi, leading them to collaborate.
Working in tandem, Maul and Pre Vizsla, the leader of Death Watch, forged the Shadow Collective. Guided by Maul's strategy, they assembled an army from diverse elements of the criminal world, including Black Sun, the Hutt Clan, and the Pyke Syndicate, all united under the Shadow Collective's banner. The Shadow Collective also crippled the Morubas crime family. To destabilize Duchess Kryze's authority, the criminal army initiated attacks on Sundari, the Mandalorian capital city, creating widespread panic and disorder as the New Mandalorian government proved unable to control the criminal elements. Death Watch then arrived, posing as saviors, rescuing civilians and police forces alike, who then regarded them as the heroes who saved Mandalore from the attacks.
Following the successful implementation of their scheme, Vizsla garnered popular support, ousted the Duchess, and assumed leadership of Mandalore. However, his ambitions led him to betray the Sith and imprison them. As his rule commenced, the planet's politicians either aligned with him or faced execution. While incarcerated, Maul formed an alliance with Almec, the former Prime Minister who had been imprisoned on corruption charges. The Sith escaped from confinement, and Maul challenged Vizsla to a duel for leadership. Vizsla accepted, and the two engaged in combat within the Sundari throne room. Maul emerged victorious, killing Vizsla and seizing his position as the leader of Death Watch. However, some Death Watch members refused to submit to Maul, resulting in open conflict within Death Watch. Maul subsequently installed Almec as Prime Minister to serve as a puppet ruler, concealing his presence from the Republic.