Complex sentence: Stauffenberg was third in line to be executed, with Lieutenant von Haeften after, however, when it was Stauffenberg's turn, Lieutenant von Haeften placed himself between the firing squad and Stauffenberg, and received the bullets meant for Stauffenberg.
Split into simpler sentences: Stauffenberg was third in line to be executed, with Lieutenant von Haeften after. However, when it was Stauffenberg's turn, Lieutenant von Haeften placed himself between the firing squad and Stauffenberg, and received the bullets meant for Stauffenberg.