historical significance: it was the first day of conscription (in Petrograd and Moscow), and the first day of combat against the occupying Imperial German Army. The Red Army also fought against national independence movements in the territory of the former Russian Empire, including three military campaigns against the army of the Ukrainian People's Republic, in January–February 1918, January–February 1919, and May–October 1920. In June 1918, Leon Trotsky abolished workers' control over the Red Army, replacing the election of officers with traditional army hierarchies and criminalizing dissent with the death penalty. Simultaneously, Trotsky carried out a mass recruitment of officers from the old Imperial Russian Army, who were employed as military specialists (voenspetsy, :ru:Военный советник). The Bolsheviks occasionally enforced the loyalty of such recruits by holding their families as hostages. As a result of this initiative, in 1918 75% of the officers were former tsarists. By mid-August 1920 the Red Army's former tsarist personnel included 48,000 officers, 10,300 administrators, and 214,000 non-commissioned officers. When the civil war ended in 1922, ex-tsarists constituted 83% of the Red Army's divisional and corps commanders. In September 1918, the Bolshevik militias consolidated under the supreme command of the Revolutionary Military Council of the Republic (). The first chairman was Trotsky, and the first commander-in-chief was Jukums Vācietis of the Latvian Riflemen; in July 1919 he was replaced by Sergey Kamenev. Soon afterwards Trotsky established the GRU (military intelligence) to provide political and military intelligence to Red Army commanders. Trotsky founded the Red Army with an initial Red Guard organization and a core soldiery of Red Guard militiamen and the Cheka secret police. Conscription began in June 1918, and opposition to it was violently suppressed. To control the multi-ethnic and multi-cultural Red Army soldiery, the Cheka operated special punitive brigades which suppressed anti-communists, deserters, and "enemies of the state". The Red Army used special regiments for ethnic minorities, such as the Dungan Cavalry Regiment commanded by the Dungan Magaza Masanchi. It also co-operated with armed Bolshevik Party-oriented volunteer units, the special task units – chasti osobogo naznacheniya – or ChON, from 1919 to 1925. The slogan "exhortation, organization, and reprisals" expressed the discipline and motivation which helped ensure the Red Army's tactical and strategic success. On campaign, the attached Cheka special punitive brigades conducted summary field courts-martial and executions of deserters and slackers. Under Commissar Yan Karlovich Berzin, the brigades took hostages from the villages of