Z-plan – the Beginnings

When Admiral Raeder took over as chief of the Reichsmarine in 1928, there was massive residual distrust in the Reichmarine, due in large part to the role the Reichsmarine played in the mutiny of 1918. But there was also the realization that the ‘Tirpitz fleet’ built in the decades before WW-I, had cost so much and achieved so little, it was not a route they wanted to repeat. Every time a naval funding issue was run through Parliament, the fiercest debates raged turning each warship into a political football. Raeder strived to establish a multi-year modest program for ship construction , so when Hitler took over, Admiral Raeder would float a concept that would eventually become the Z Plan and not be completed before 1949. Hitler had openly stated his opposition to any naval funding due to the damage this funding had on WW-I. He envisaged the Reichmarine as a purely coastal defense force.

It took all Raeder could do, to get Hitler to at least reconsider the Reichmarine role in the new Reich. Hitler also harbored a fantasy that the strategic conflict with the UK, could be avoided if a deal could be struck. He imagined this deal focusing on Germany avoiding any conflict with the UK, and in return Hitler was given a free reign in Eastern Europe. He even believed the UK and Germany could form an alliance against the USA. Needless to say the UK and the USA made it clear they would not allow Hitler a free hand anywhere as early as 1935…but Hitler clung to his believe that they would change their minds ‘when the chips were down’. This was not that different for the fantasy most of the 1920s German generals had surrounding the League of Nations bailing Germany out of any war with Poland. At worse Hitler believed he could avoid direct confrontation with the UK until the mid-1940s, when Germany would be more prepared for war with the west. This despite the fact that in WW-I, war with France had immediately implied war with the UK and its Commonwealth and indirectly America.

In the Schleicher-Mueller Government, Defense minister Groener had forced the Reichmarine Admirals to craft a naval force & doctrine able to dominate the Baltic Sea and prevent the Polish and French navies from working together against Germany in any future war. In this way he could argue that it contributed directly to ‘national security’ and get the cabinet to committee to multi-year stable funding that allowed the light cruisers and pocket battleships to be built. Admiral Raeder took this idea one step further, if he could not prepare for the inevitable direct war with the UK , he would instead redirect the Reichmarine towards defeating the French or Italian navies in European waters and interdicting the overseas French commerce. …but he dropped hints that this force would be geared towards a later war with the UK. Hitler approved and the planning process began. Raeder’s initial 1934 plan he drew up was for:
8 x pocket battle cruiser
3 x aircraft carriers
18 x cruisers
48 destroyers and a total of 72 U-boats

But this was not enough, within a year many meetings of the Admiral s changed the thrust of the discussion. Raeder using the French navy as reference demanded parity with the French fleet or a navy 1/3 the size of the RN fleet. The Admirals interpreted this as 35% and later after study reported 50% of the RN fleet was needed. Already the focus had shifted from France to the UK, for the upcoming “1935 Naval Treaty”. Strategies for using this force were as diverse as the Admirals. Donitz proposed 300 U-boats , while Heyes proposed a fleet of dozen surface raiders loosely operating with U-boat flotillas , while Admiral Carls proposed four Carrier groups each with an aircraft carrier, a battle cruiser , a heavy cruiser a couple of flotillas of destroyers and several U-boat flotillas. With Hitler’s promise of unrestrained rearmament, the Admirals placed their orders and before long all the capital ship yards were full. But the orders appeared geared to fill all the strategies at the same time, while Hitler muddled things further by demanding more and bigger battleships at the expense of surface raiders and air craft carriers. On order were two 35,000 ton 11” gun battleships, two 50,000 ton 15” gun battleships; two 30,000 ton Aircraft carrier; 5 x 18,000 ton 8” gun heavy cruisers and 5 x 20,000 ton fleet tankers. That’s 11 capital ships and 5 giant Auxiliary tankers.

Meanwhile the smaller escort ship yards received orders for 36 U-boats totaling 14,000 tons and ~ 20 Destroyers plus 17 Torpedoboot as well as at least 20 smaller coast craft. For the first time in decades the naval shipyards were filled to capacity. The hulls for the capital ships should have taken 2-3 years from keel to launching with another year to commission, while the escorts should have taken 2-3 years to complete and the coastal craft 18-24 months. In practice the supply of steel needed to sustain this level of production fell to about ½ the construction needs and ended up delaying completion by 1-2 years. So by war time only ½ of the capital ships and escorts were completed when they all should have been commissioned by 1940. What went wrong?

Steel production through the late 1930s stabilized at ~20 million tons per year however increasing amounts of steel was being diverted to construction projects like the barracks housing for the extra 2 million soldiers needed for the ever expanding Heer, while the ‘Westwall’ fortification consumed enough steel to finish the capital warship program on schedule. The ammo needed for the ballooning Heer fell further behind so much that by the late 1930s at most 2 weeks supplies were available for the divisions. By the start of the war 1/3 of all war related industry was being poured into construction and the amount of money being spent each year on housing was equal to the amount of funds spent on armaments. The whole rearmament program was spiraling out of control, due to a lack of a central direction and strategy, which is a political animal.

But Admiral Raeder was not finished yet. In 1936 he added two more aircraft carriers and 6 x 50-60 ,000 ton ; 16” gun battleships plus a couple of light cruisers to the orders, even though , due to the delays none could even be even laid down until 1938- 1940. After May 1938 Czech crisis, Hitler started to make noises that maybe the UK would have to be attacked sooner than expected….although he still clung to the believe that they would remain neutral. Hitler conceded that the Autarky economic goal would likely not be reached in the short term and traditional supplies of resource would have to come by sea during war time, which meant enlarged convoy escort fleet. But Hitler also demanded more and bigger battleships. German naval strategy was lost.

Admiral Heyes had presented his doctrine based on combining a fleet of a dozen pocket battleships with 2-3 dozen light cruisers and scores of U-boats to operate in the North and South Atlantic and interdict UK shipping lanes. At that time the Kriegsmarine [KM] had only 3-5 x surface raiders and would only get 2 more before the expected 1940 Wehrmacht operational date. Worse the cruiser fleet at that time would be less than a dozen warships of which ½ were light cruisers with structural weakness that limited sea worthiness in the open ocean, due to welded construction. Even with an unrealistic construction plan, such a fleet could not be realized before 1944/45.

Despite the completely unrealistic political assumption imbedded in the Heyes strategy, this became the basis of the KM so called “Z Plan” as it approached war, augmented by Donitz limited U-boat fleet. Although alternatives to the Z plan were proposed they all evolved around slight changes to the ratio of battleships to pocket battle cruisers. Admiral Raeder tried several times to present this plan to Hitler , but Hitler harshly criticized the plan due to lack of battleships sending Raeder back to the admirals . Raeder tendered his resignation which Hitler clearly rejected. The planned fleet at that point was 365 warships completed by 1949, just above the WW-I Imperial fleet of 324 warships. In October 1938 the revised “Z Plan” included
10 battleships
15 pocket battle cruisers
5 heavy Cruisers
24 light cruisers
36 small cruisers
8 aircraft carriers
249 Submarines
Not mentioned are the 70 destroyers and 78 Torpedoboot also planned along with another 300 other smaller warships.

By then the war had begun and everything changed. Europe was overrun quickly meaning economic autarky was already de facto in place and the large overseas escort fleet was not need. Worse since Hitler and Goering believed the war was already won , there was no need to go to war with the UK, so the whole Z plan was cancelled since most of the ships would be completed after the war. Over the 1930s the German navy had suffered from lack political trust from the past, a lack of consistent resource allocation or long term planning to ship construction, a lack of Admiral consensus on the best approach and a lack of support from Hitler on the course that was chosen. Wilhelm Deist describes their reaction to all these stress and strains as ‘autistic’ and that’s what Germany got, an ‘Autistic navy’.

Sources :
"Germany and the Second World War" Vol-1 [Ed : Deist, Messerschmitt, Volkmann and Wette]
"The German Military in the age of Total War" Wilhelm Deist
"The Wehrmacht and German Rearmament " Wilhelm Deist
"War and Economy in the Third Reich" Richard Overy.
The Oxford Companion to World War-II [Ed: Dear and Foot]