Charles Xll of Sweden ignored the advice of his generals to retreat before the army of Tsar Peter l [the Great]. Charles hoped that the superior experience of his troops and total surprise would enable his 19,000 to defeat the Tsar's 42,000.
Rather than attempt to defend Charles went on the attack. In spite of great courage the attack failed, Charles fled and the Swedish army was almost eliminated.

The city of Poltava, in the Ukraine. (Ukraine)

Russian Army

Number engaged :

42,000

Casualties :

4,735 (11.27%)

Swedish Army

Number engaged :

19,000

Casualties :

9,661 (50.85%)