The "Day of Defeat" series of games take place during which war?

The Day of Defeat series of games takes place during World War II because they are inspired by the events and battles that occurred in this global conflict. The games aim to immerse players in the intense and chaotic battlefield of World War II, allowing them to experience the struggles and challenges faced by soldiers fighting in this war. From the iconic D-Day landings to intense urban warfare, the Day of Defeat series recreates the historical setting and enables players to engage in fast-paced multiplayer combat in the context of this war.