Song name: My Pierwsza Brygada(Real translation: We are the 1st. Brigade; In Polish, My means "We, Us"(Russian:Мы первая бригада)
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Singer's Name: Eugeniusz Mossakowski(1st. June 1885; Łodz - 13 May 1958; Warszaw); Polish Opera Singer from the Grand Theatre (Teatrze Wielkim w Warszawie).
"One of the best baritones in Europe in his generation. He sung in the Grand Theatre in Warsaw in years 1921-39, although his artistic career had been started by him in late years of his life, after he was 32 years old. After the 2nd World War, he withdrew from the artistic career and devoted himself entirely to teaching."
My, Pierwsza Brygada (We [are] the First Brigade) was a song of the First Brigade of the Polish Legions, led by Jozef Pilsudski. It is also known under the title “Legions are a soldier’s note”.
The melody is taken from the March of the Kielce Fire Department. Capt. Andrzej Brzuchal-Sikorski, who since 1905 was a Leader of the orchestra of Kielce Fire Department, and later – of the orchestra of the First Brigade of the Polish Legions of Józef Pilsudski - was the first performer and arranger of the song. “My Pierwsza Brygada” was regarded in the years after World War 1 almost the national anthem of Poland. In 2007, the Minister of National Defence decided, that “My Pierwsza Brygada” becomes a parade song of the Representative Corps of the Polish Army.
The First Brigade of the song were a Polish Unit of the Austro-Hungarian Army. "The First Brigade was formed on December 19, 1914, as part of the Polish Legions in World War I. Until October 1916 the First Brigade was commanded by Józef Piłsudski, thereafter by Marian Żegota-Januszajtis. The First Brigade and the Third Brigade were disbanded after the 1917 Oath Crisis.
The March of the First Brigade was one of the best-known songs of the Polish Legions." - English Wikipedia.

Here's the original recording without leaping: