Directive for the Strategic Concentration “Green”

The Directive for the Strategic Concentration “Green” is Adolf Hitler’s military plan for an attack on Czechoslovakia, organized around speed, surprise and the rapid defeat of Czech resistance. Revealed to British officials during the Sudeten crisis, it gives operational substance to the threat of invasion and sharpens the dilemma facing Neville Chamberlain’s government: whether to deter Hitler, or to press Czechoslovakia to yield before the threatened deadline.

Purpose and Strategic Design

The document’s stated objective was to create, within the first two or three days, a situation that would demonstrate to any states considering intervention that the Czech military position was hopeless. Its emphasis was not simply on taking territory, but on moving quickly enough to prevent outside powers from changing the military balance. The timing made speed itself a strategic instrument: a rapid defeat was meant to narrow the opportunity for intervention.

The directive called for formations capable of rapid deployment to force the frontier fortifications and break boldly into Czechoslovakia. The bulk of the mobile army was then to follow as quickly as possible. This sequence joined an initial assault to a swift buildup, aiming to turn the first breach into a wider advance before the defenders or their potential allies could respond effectively.

Air and land operations were to begin together. The Luftwaffe was assigned its main strength in a surprise attack against Czechoslovakia, with aircraft crossing the frontier at the same time as the first army units. The plan therefore treated surprise not as a preliminary flourish but as part of the invasion’s central method: simultaneous pressure from the air and ground would help produce the early collapse the directive sought.

Disclosure and Assessment

The directive was brought into the British deliberations while the crisis was intensifying. Its heading identified a “War on Two Fronts with Main Effort in the South-east” and named the strategic concentration “Green.” Hugh Legat saw a senior military reader sit bolt upright at the document’s contents. When its source was questioned, the account given was that it had been put through a letterbox at a private home about thirty minutes earlier.

Sir Alexander Cadogan cleared space on the table and read the pages closely, turning each one over and arranging it to his right. His German was good, and his earlier service in charge of the embassy in Vienna in the summer of 1914 gave the scene a pointed historical echo. At the document’s end, he raised the question of whether it was genuine; the response was that it certainly seemed so. The exchange records both the document’s immediate force and the need to distinguish an alarming plan from a verified one.

From Military Plan to Diplomatic Pressure

The directive arrived against a public and diplomatic deadline. Chamberlain told ministers that Adolf Hitler had rejected even a short wait for the orderly transfer of the Sudeten territory, which the Czechoslovak Government had accepted subject to a plebiscite, and had announced an invasion for Saturday. Chamberlain also reported that, after Sir Horace Wilson warned him that Britain might have to support France if it fulfilled its treaty obligations to Czechoslovakia, Hitler had answered that he was prepared for every eventuality and that war could come by the following Monday.

The British government considered whether to mobilize before Germany. When asked how soon it could be operational by 1 October, the answer was that it would have to be done that day. Chamberlain warned that even partial mobilization would mean Britain mobilizing first; its advocate argued that it could show Hitler Britain was not bluffing and might make him reconsider. Chamberlain, drawing on his two meetings with Hitler, feared that such a signal might instead push him into war because he could not tolerate losing face. The directive’s immediate military timetable thus sat beside a dispute over whether visible preparation would deter aggression or accelerate it.

The Limits of Concession and Delay

Sir Horace Wilson proposed a telegram urging the Czechoslovak Government to accept Hitler’s terms before his two o’clock deadline the next day and withdraw from the Sudetenland. He argued that this was the surest way to avoid Britain being drawn into a war that might expand enormously. Chamberlain, meanwhile, questioned how the British public could be persuaded to continue a winter war if Czechoslovakia collapsed before the end of October, particularly after Britain had already conceded the case for transferring the Sudeten Germans from a Czech-dominated state.

Lord Halifax opposed Wilson’s proposed telegram. He said he could not in good conscience support telling the Czechs to surrender territory under threat of force, calling that complete capitulation. He acknowledged that refusing might make war certain, but argued that Britain could not urge what it believed wrong, that the House of Commons might reject the proposal, and that there was no firm guarantee the German Army would stop at the Sudetenland rather than occupy the whole country. The issue was therefore not only whether the invasion plan could be delayed, but whether a concession could offer any reliable limit to Hitler’s advance.

A further pause came through Benito Mussolini. At seven minutes past two, Sir Nevile Henderson telephoned from Berlin to report that Mussolini had sent Hitler a message promising Italy’s support in the event of conflict while asking for a twenty-four-hour postponement of mobilization so the situation could be reconsidered. Hitler had agreed. In Sir Horace Wilson’s later account of the meeting with Hitler, Hitler continued to present the crisis as requiring settlement by Saturday, watched his clock as if measuring the remaining pause, and demanded either a guarantee that the Czechs would begin evacuating the disputed territory or a German march into it. The delay changed the immediate clock, not the underlying threat. The directive remains significant in this context because its detailed plan exposes the military force beneath the demands and deadlines, while British ministers struggle to find a response that will not itself precipitate war.