"Papa Jack started his military career as a footsoldier in The Great War. Afterwards, he became a mechanic, but rejoined the army when he couldn't make ends meet."
— Call of Duty 3 bonus materials section.
Papa Jack first appears in a cut scene where he explains to the tank crew why they cannot just go right after Richter, or also known as the "The Black Baron". Kolwalski suggests to just cut off Richter's supply line, Papa Jack merely says "For that, we rely on the British", causing most of the tank crew to scoff at the idea. As they have news of Richter's supply line being cut off and the arrival of air support, Papa Jack and his Battle group pushes into town, where the Black Baron is. After a ferocious duel and battles with the Black Baron and his tanks, Papa Jack and the Tank crew becomes victorious and Kolwalski calling Richter "The swinia (Polish for pig) who drove us from the motherland" after the battle is over. Soon after, the 1st Division is ordered to take "The Mace" or Mount Ormel. Then they are to secure the hill from countless impeding forces of German troops and tanks, as they furiously tried to defend the hill, their firefly is damaged and Bohater, Ulan, and Rudinski are forced to regroup with Papa Jack and the rest of the group. As they where all in a secluded bunker, a Tiger tank makes a direct hit to the bunker, killing Kolwalski, and nearly taking Papa Jack's life. As they are pushed further back and having lost Rudinski along the way, they are on the top of the Mace and was on the verge of losing it, but were then saved by the arriving Canadian forces. As Lt. Robiechaud and Papa Jack have a conversation, It shows that he had a family-like relationship with the tank crew mates while distraught of having most of them died defending Mount Ormel. He respected his men for their sacrifices and wanted to bring them back to Poland to bury them.