Russian Empire
The Russian Empire, also known as Imperial Russia or simply Russia, was an empire that existed across Eurasia and North America from 1721, following the end of the Great Northern War, until the Republic was proclaimed by the Provisional Government that took power after the February Revolution of 1917.
1st Army (Russian Empire)
The 1st Army () was an army-level command of the Russian Imperial Army created during World War I. The First Army, commanded by General Paul von Rennenkampf, invaded East Prussia at the outbreak of war in 1914 along with the Second Army commanded by General Alexander Samsonov. After declaring war on the German Empire, the Russian Empire had been able to mobilize very quickly. All Russian forces were put under the command of Grand Duke Nikolai and his Quartermaster General Yuri Danilov.