In order to attempt to understand what WWII soldiers endured, the lead group of actors were required to participate in a 10-day boot camp. This bootcamp was run by the film’s military advisor, the retired former USMC Captain Dale Dye. Dye led all of the actors on marches, living in tents, intensive field combat situations, and also eating MREs. Moreover, the team received tactical training which involved learning how to clean, assemble, and fire weapons for that time period.
But Not You
Speaking of bootcamp, Matt Damon was the only one intentionally not brought into the camp. The reason? Spielberg wanted to make the rest of the crew feel resentment towards his character – as they were risking their lives to save him in the movie.