Complex sentence: The decision for an offensive of some kind was made by the General Staff, and Ludendorff himself, the German government and Hindenburg himself were not party to the planning process.
Split into simpler sentences: The decision for an offensive of some kind was made by the General Staff, and Ludendorff himself. The German government and Field Marshal Paul von Hindenburg, nominally the Chief of the General Staff, were not party to the planning process.