was the case. According to the concept of Boris Shaposhnikov, chief operations manager on the Field Staff of the Revolutionary Military Council, the Soviet leadership decided to concentrate forces in Belarus and launch a counteroffensive from there. The Polish challenge in Ukraine necessitated a Soviet response. Leon Trotsky arrived at Mogilev to personally motivate Russian troops to avenge the Polish insult. He predicted the Red Army's presence in Warsaw in the near future. On 14 May, Trotsky ordered the Red Army to attack. Mikhail Tukhachevsky, the young, accomplished in fighting the Whites former lieutenant in the Imperial Russian Army, was made commander of the Western Front on 1 May 1920. He wanted to launch an assault on the Belarusian front before Polish troops arrive from the Ukrainian front. On 14 May, Tukhachevsky's so-called first offensive began. Western Front's 15th and 16th Armies attacked the slightly weaker Polish forces (the combatants had respectively 75,000 and 72,000 combined infantry and cavalry soldiers at their disposal) and penetrated the Polish-held areas to the depth of one hundred kilometers. The transfer of two Polish divisions from the Ukrainian front had to be expedited and the newly formed Polish Reserve Army (32,000 men) was used after 25 May. Because of the energetic Polish counter-offensive led by Stanisław Szeptycki, Kazimierz Sosnkowski, and Leonard Skierski, by 8 June the Poles had recovered the bulk of the lost territory, Tukhachevsky's armies were withdrawn to the Avuta and Berezina Rivers, and the front had remained inactive until July. While Tukhachevsky retained control of the strategic points needed for future offensive action, the Polish high command kept its ineffective system of linear arrangement of forces and weak rear reserves. The Soviet forces south of Polesia were also getting ready for a counterassault. On 5 May, Felix Dzerzhinsky arrived in Kharkiv and brought with him 1,400 Cheka functionaries, charged with improving discipline in Red Army units. The plan for the counteroffensive in the south was approved during a 15 May conference in which Sergey Kamenev also participated. Because the 12th and the 14th Armies of the Southwestern Front still did not have sufficient resources to launch an attack, the participants decided to wait for the arrival of the 1st Cavalry Army under Semyon Budyonny, which was on its way (from 10 March) to the Polish–Soviet combat area. The 1st Cavalry Army, a highly regarded formation credited with the destruction of Anton