1st Army (Russian Empire)

Army · Russian Empire · July 30, 1914 – March 3, 1918

Paul von Rennenkampf's army, which invaded East Prussia from the east in 1914.

August 17, 1914 Invades East Prussia Map
August 17 – September 14, 1914 Russian invasion of East Prussia (1914)
August 17, 1914 Battle of Stallupönen
August 20, 1914 Battle of Gumbinnen Wins at Gumbinnen Map
August 26–30, 1914 Battle of Tannenberg
August 27, 1914 Advances slowly toward Königsberg Map
September 10, 1914 First Battle of the Masurian Lakes Driven out of East Prussia Map
September 20, 1914 – November 10, 1914 Behind the Niemen Map
November 20, 1914 Battle of Łódź (1914) Tries to cut off the Germans at Łódź Map
January 31, 1915 Battle of Humin-Bolimów
February 18 – March 26, 1915 First Battle of Przasnysz
July 13 – August 24, 1915 Bug–Narew offensive
August 26 – October 2, 1915 Battle of Vilnius (1915)
September 1, 1915 Holds the northern front after the Great Retreat (approximate) Map