Baron Pavolski was outraged by the Nazi atrocities that were committed in his homeland of Poland. The Marksman was born when the Nazi's invaded his ancestral mansion for a base of operations.
By day he masqueraded as Major Hurtz, loyal party member, by night he was The Marksman. His noble birth granted him the training of sword and bow. He worked under cover throughout Europe and aided members of the Justice Society of America.
His post World War 2 exploits have not been recorded.
In JLA Destiny he joined the fledgling Justice League, a group funded and founded by Thomas Wayne.
The Marksman had no superhuman powers. He demonstrated exceptional skill with a bow and arrow. Sometimes he employed "trick" arrows such as an explosive arrow and he could shoot multiple arrows at once. He was also an above average athlete and combatant. As Major Hurtz, Baron Povalski was skilled in the art of disguise.