Revolutionary Insurrectionary Army of Ukraine
In the late autumn of 1918, Zadov returned to Ukraine and joined Nestor Makhno's guerrillas in August 1918 and quickly became chief of the Kontrrazvedska, the military intelligence of the Revolutionary Insurrectionary Army of Ukraine. According to numerous eyewitnesses, he was a member of Makhno's inner circle and friend of Makhno's wife. Zadov is credited with personally saving Makhno's life several times during skirmishes with Red Army forces.