The 1st Army () was an

army An army, ground force or land force is an armed force that fights primarily on land. In the broadest sense, it is the land-based military branch, service branch or armed service of a nation or country. It may also include aviation assets by ...

-level command of the

Russian Imperial Army The Imperial Russian Army () was the army of the Russian Empire, active from 1721 until the Russian Revolution of 1917. It was organized into a standing army and a state militia. The standing army consisted of Regular army, regular troops and ...

created during

World War I World War I or the First World War (28 July 1914 – 11 November 1918), also known as the Great War, was a World war, global conflict between two coalitions: the Allies of World War I, Allies (or Entente) and the Central Powers. Fighting to ...

. The First Army, commanded by General Paul von Rennenkampf, invaded

East Prussia East Prussia was a Provinces of Prussia, province of the Kingdom of Prussia from 1772 to 1829 and again from 1878 (with the Kingdom itself being part of the German Empire from 1871); following World War I it formed part of the Weimar Republic's ...

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 German Empire (),; ; World Book, Inc. ''The World Book dictionary, Volume 1''. World Book, Inc., 2003. p. 572. States that Deutsches Reich translates as "German Realm" and was a former official name of Germany. also referred to as Imperia ...

, the

Russian Empire The Russian Empire was an empire that spanned most of northern Eurasia from its establishment in November 1721 until the proclamation of the Russian Republic in September 1917. At its height in the late 19th century, it covered about , roughl ...

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. The invading forces made a determined and speedy attack on East Prussia. However, the First and Second Armies were stopped by the German Eighth Army, led by Field Marshal

Paul von Hindenburg Paul Ludwig Hans Anton von Beneckendorff und von Hindenburg (2 October 1847 – 2 August 1934) was a German military and political leader who led the Imperial German Army during the First World War and later became President of Germany (1919� ...

and his chief of staff, General

Erich Ludendorff Erich Friedrich Wilhelm Ludendorff (; 9 April 1865 – 20 December 1937) was a German general and politician. He achieved fame during World War I (1914–1918) for his central role in the German victories at Battle of Liège, Liège and Battle ...

. The German and Russian armies met at Tannenberg, where the Second Army was encircled and suffered complete destruction. Both the First and Second Armies suffered terrible casualties in one of the most comprehensive German victories of

. The First Army also suffered defeat at the First Battle of the Masurian Lakes in September 1914, which led to Rennenkampf's dismissal and replacement by Litvinov. First Army served under Northwestern front for the remainder of the war. Litvinov was replaced by Sokovnin in April 1917. Vannovski replaced Sokovnin in July and the army's final commander, von Notbek, took over in September 1917.

Order of battle on formation

The First Army consisted of the following units in August 1914:

Military Fronts in which the 1st Army participated

Northwestern Front The Northwestern Front (Russian: ''Северо-Западный фронт'') was a military formation of the Red Army during the Winter War and World War II. It was operational with the 7th and 13th Armies during the Winter War. It was re-c ...

(July 1914 – August 1915) * Western Front (August 1915 – April 1916) * Northern Front (April 1916 – July 1917) * Southwestern Front (July – September 1917) * Northern Front (September 1917 – the beginning of 1918)

Engagements

* Battle of Stallupönen (17 August 1914) * Battle of Gumbinnen (20 August 1914) *

Battle of Tannenberg The Battle of Tannenberg, also known as the Second Battle of Tannenberg, was fought between Russia and Germany between 23 and 30 August 1914, the first month of World War I. The battle resulted in the almost complete destruction of the Russ ...

(23–30 August 1914) * First Battle of the Masurian Lakes (8–11 September 1914) * Battle of Łódź (11 November – 6 December 1914)

Commanders

The 1st Army had the following commanders until it was demobilized in 1918.

References

{{Russian Empire Ground Forces Military units and formations established in 1914 1914 establishments in the Russian Empire Military units and formations disestablished in 1918 01

Order of battle on formation

Military Fronts in which the 1st Army participated

Engagements

Commanders

See also

References