Beginnings of Czechoslovak Signal Corps are connected namely with the operation of Czechoslovak Legions in Russia. Czechoslovak Telegraph Company occurs in the initial organisational plans of the future Army Corps as early as at the end of July 1917. However, when the Czechoslovak Army Corps, consisting of two divisions, was established on the basis of the Order of the Chief of Staff of Supreme Commander of Russian Forces, No. 613, dated October 9 (September 26) 1917, no telegraph company existed in its formation yet. October 30 (17), 1917 became a historical day for the foundation of the future Czechoslovak Signal Corps. Based on the Order No. 931 of the Chief of Staff of Supreme Commander of Russian Forces Lt. General Nikolaj Nikolayevich Duchonin, they established Czechoslovak Telegraph Company that day.