The Mandalorian Civil War began in Sundari, the capital, after the Shadow Collective deposed Duchess Satine Kryze and her New Mandalorian administration. To determine who would control Mandalore, Maul challenged Pre Vizsla, the leader of Death Watch, to a duel for leadership. Although Maul was victorious, having killed Vizsla in combat, not all Death Watch members accepted this sudden change in command. Bo-Katan Kryze, the Duchess's sister and loyal to Vizsla, transformed her forces into the Mandalore resistance and revolted against Maul, thus starting the conflict. Obi-Wan Kenobi participated in the Battle of Mandalore, as did Darth Sidious, who engaged Maul and his brother, Savage Opress, in battle. During this battle, Darth Sidious killed Savage, and then captured Maul, imprisoning him in the Spire on Stygeon Prime.
Despite the attempts by Prime Minister Almec to discredit former Duchess Satine Kryze by falsely accusing her of abandoning her pacifist beliefs to murder Vizsla, thereby concealing Maul's actions, Maul's execution of Satine Kryze sparked a rebellion among many Mandalorians. They united to liberate Mandalore from the outsider who had seized control. Even as the civil war consumed Mandalore, his Mandalorian super commandos freed Maul, but his mother, the powerful Nightsister Talzin, was soon killed during the Second Battle of Dathomir. Maul went back to Mandalore, but the Galactic Republic and the Mandalore resistance besieged the planet. After Maul was captured, Kryze took control of the planet. However, she would eventually lose her position when she refused to submit to the Galactic Empire, which initiated an occupation of Mandalore using the clone forces already present.