WW2: Time of Wrath
There are four campaigns that can last until 1948: 1939 Grand Campaign, 1940 Fall Gelb, 1941 Barbarossa and 1944 Gotterdammerung; 2 short introductory scenarios (Fall Weiss and Overlord), and one tutorial added through a later patch. The game can end before the time limit if the human-controlled country is defeated or there is only one Alliance left standing. When reaching 1948, the winner is determined by counting each faction's Victory Points, which one gains when conquering a city on the map.
The gameplay is pretty easy to understand and is reduced to controlling cities and resources, from which Production Points are generated, investing them in either military units or research, moving your forces and attacking enemy units, taking certain diplomatic actions and occasionally making historical decisions like a land cession, for example.