On Sunday, the Philadelphia Eagles will play in their seventh NFL championship game — known as the Super Bowl for the past 52 seasons — since 1947. Because this occasion is so rare, it seems appropriate to take a moment to acknowledge the previous six great Eagles teams.

Here’s a look back at the first three, all from the pre-Super Bowl era.

Battle of the Birds, Episode 1: A New Hope

Date: December 28, 1947

Location: Comiskey Park, Chicago

Final Score: Chicago Cardinals 28, Philadelphia Eagles 21

In the post-World War II era, football was a different game. Linemen rarely weighed more than 250 pounds.

Helmets had just been recently introduced, and the possibility of permanent brain injury was not even a thought. Future Pro Football Hall of Famer Steve Van Buren carried the Eagles to their first playoff berth, leading the NFL in carries (217), yards (1,008) and touchdowns (13).

Van Buren was selected as a first-team All-Pro. After having so much success on the ground in the regular season, the Eagles relied heavily on quarterback Tommy Thompson in the championship game.

Thompson threw for 297 yards, an impressive feat at the time considering the league’s leading passer averaged fewer than 250 passing yards per game, but the Eagles lost in front of a crowd of over 30,000.