From the end of the Second World War historians have sought to answer one of its most intriguing questions: to what - and to whom - did the Wehrmacht owe its shocking initial operational successes? What was the nature of German strategic and operational perceptions, and were they new — or even, as some researchers have suggested, 'revolutionary'? Was German post-1918 military culture conducive to a thorough investigation of past mistakes, a re-evaluation of traditional notions, and the pursuit of new ideas? In reality the Reichswehr officer corps jealously defended its inherited conceptual boundaries, retreated ever-deeper into a one-dimensional self-perception and strategic outlook, and offered conceptually ossified solutions to the Republic's pressing security problems. German officers, convinced that their doctrine and military world-view were flawless, never challenged the axioms and values that had brought army and nation to catastrophe in 1918: extreme warfare, culminating in the most destructive and eventually self-destructive actions; extremes of risk-taking; the endless pursuit of annihilational battles that dictated the reduction of strategy to meticulous operational and tactical planning; the trust in 'spiritual superiority' to overcome enemy advantages in material and manpower; ruthlessness; and an exaggerated drive for action at all costs. Idiosyncratic operational planning that was at times completely detached from strategic reality completed the picture of a military organisation unable to renew itself. No comprehensive analysis has yet convincingly explained this astonishing continuity, or linked it to the allegedly innovative operational theory and doctrine that evolved in the second half of the 1930s. The concept of military and organisational culture can however provide the necessary theoretical foundations for understanding both that continuity and the doctrinal shape that it assumed in the imminence of the Second World War. It can explain - as this thesis demonstrates - the disastrous and seemingly inexplicable wrong-headedness of a group of otherwise highly intelligent men.