The event covers B.J. Blazkowicz initial infiltration of the SS Tirpitz, it explains how he sabotaged the ship, how he got the captain's uniform and how he found the medallion. It ends with "To Be Continued" and more or less is required to fully understand the Intro to the game.
The framing story about the Fourth Reich places the events of story after the events of Spear of Destiny, Return to Castle Wolfenstein and Wolfenstein 3D (in that order chronologically but played in the order of Wolf3D, SoD, and RTCW in the first three episodes of the comic). However, the actual game is not clear on the date of the game, and one of the only given dates in the game is referenced on the Leichenfaust 44 suggesting that the weapon was first designed/manufactured in 1944, and the propaganda posters that mention September 3, 1944.