sentences:  Despite considerable Soviet efforts to crush the rebellion, the Don Cossack insurgents managed to hold out until the Don Cossack Army was able to go over to the offensive and relieve them in early June.Meanwhile, the Volunteer Army in the Donbas region was also able to go over the offensive, managing to take Kharkiv on 25 June, Kursk on 20 September and Oryol on 13 October.On the eastern end of the AFSR’s front, the Caucasian Army under Baron Pyotr Wrangel captured Tsaritsyn on 30 June.