Lennart Torstensson, Count of Ortala, Baron of Virestad (17 August 1603 – 7 April 1651), was a Swedish Field Marshal and military engineer. Torstensson was a famed understudy of Gustavus Adolphus, who in his early career primarily managed the king's artillery brigades.
In April, 1632, on the eve of the Battle of Rain, Torstensson took possession of cannons provided by a delegation from the New United States. Torstensson was astonished by the quality of the guns, and was pleased at how they handled on the battlefield the next day.
Torstensson would later become commanding general of the USE Army. During 1634, Torstensson led his army in the decisive defeat of the French Army at the Battle of Ahrensbök.
In 1635, Torstensson led the First and Second Divisions of the USE Army into Brandenburg, and then into Poland. As of March 1636, he was still there, outside the city of Poznań.