Throughout a summer in which tension with Poland was stimulated by German agencies, Heinz Guderian and his staff were preoccupied with plans for major exercises in which the mechanised divisions were to be tested as never before, manoeuvres which demanded the initial stages of mobilisation. Crew training, however, was far from complete in every unit and while they had over 3,000 tanks with which to play, only 98 of them were Pz Ills and 211 Pz IVs, and therefore most were the light Pz Is and IIs. But the latest communication systems had arrived almost to scale and improvements had been made to the supply services. Then came a change that can hardly have been unexpected. On 22nd August Guderian was ordered to take command of the newly formed XIX Corps (with Nehring as Chief of Staff) at Gross-Born and, under the cover title of ‘Fortification Staff Pomerania’, build field fortifications along the frontier with Poland. Next day Hitler announced the signing of a non-aggression pact with Soviet Russia and ordered the Army to attack Poland on the 26th. Preparations would be incomplete and mobilisation only in the preparatory stages, but the mechanised units were ready: some had been fully mobilised since July.
Poland’s ability to defend herself depended mainly upon a fiery determination to preserve her newly won independence. Of modern weapons she had few – a mere 225 tanks, not all of them modern, and only 360 aircraft to set against Germany’s 1,250. For combat technique she relied upon the sort of linear defence and positional warfare by horse and foot armies which had been the fashion in 1920, and which still largely dictated the methods of her allies in the West – the French and the British. From them she could not expect speedy help since they would take weeks to mobilise the massed-style armies of a previous epoch; nor was she likely to assemble her own full strength of 45 divisions and 12 brigades in the short time permitted by the Germans. It was about to be revealed to an astonished world that, for special reasons, Poland never had a chance; that six Panzer Divisions and four Light Divisions aided by massive air intervention could achieve in a few days what the remaining 45 German cavalry and infantry formations might never have accomplished in weeks. As Professor Michael Howard has said, ‘The Germans were almost unique in 1939-40 in that they appreciated with the minimum of practical experience … the full implications which the new technological developments held for military science and embodied them in their equipment and their doctrine. I find it difficult, off hand, to think of a comparable example. Usually everybody starts even and everybody starts wrong.’ If Howard had substituted ‘Guderian and his adherents’ for ‘the Germans’ he would have been precisely accurate.
Ironically, though symbolically, Guderian was to be denied a part in the main initial armoured drive which was directed by Generaloberst Gerd on Rundstedt’s Army Group South (Chief of Staff, von Manstein) with two Panzer and three Light Divisions from Silesia towards Warsaw. In so-called good tank country Guderian’s old XVI Corps, commanded by General der Kavallerie Erich Hoepner, was told to lead the assault and was to make striking progress from the moment it was launched on 1 st September – the alteration from 26th August being enforced by diplomatic circumstances. Guderian’s XIX Corps, with its single panzer division – the 3rd – and its 2nd and 20th Motorised Divisions (which had no tanks was to be sent as the spearhead of Army Group North (Generaloberst Fedor von Bock) and Fourth Army (General der Artillerie Gunther von Kluge) against far tougher opposition on a potentially less lucrative mission into the strongly defended Polish Corridor where fortifications made good use of the delaying effect of two river obstacles – the Brahe and the Vistula. Yet it was the magnitude of an awkward task which gave Guderian, from the outset, the opportunity to demonstrate with a minimum of time for preparation, the versatility of his creation.
On the 24th – the eve of battle as he erroneously took it to be – he wrote a bracing letter to Gretel: ‘We have to keep our ears stiff and be prepared for strenuous work. I hope all will turn out well and also quickly … As regards the Western Powers it is not clear what they will do though surprises are not out of the question, but now we can bear that with fortitude. The whole situation has improved considerably and we can go to work full of confidence …’ – an approving reference to the Soviet Pact which he welcomed as a re-establishment of the bridge with Russia. He realised how her mother’s heart would be worried for their two sons, both of whom were in the Army and soon to receive their baptism of fire along with the Panzertruppe. But ‘Please be a brave soldier’s wife and, as so often before, an example to other people. We have drawn the lot to live in a warlike way and now have to put up with it’.
Nowhere does Guderian show remorse for the Poles. It would have been surprising had he done so. Poland was an excrescence to many Prussians, a nation which had come into being at the expense of the tribal homeland. Since 1918 they had posed a constant threat to Germany’s eastern frontier: Frontier Defence Force East had been as much concerned with checking depradations by the Poles as by the Bolsheviks. And Guderian was particularly pleased to play a part in recapturing the old family property. His letter to Gretel indicates how ‘… the old family estates, Gross-Klonia, Kulm now take on a special significance … Is it not strange that I especially have been commissioned to play this role’. But he cannot have had detailed knowledge of the briefing of the Commanders-in-Chief by Hitler on 22nd August, although no doubt he was aware that Brauchitsch had promised the Führer ‘a quick war’. So, likely though it is that he was informed through the usual flow of news circulating in higher military circles that the British and French might be intransigent, it is unlikely he heard then that Hitler had also pronounced on the 22nd: ‘I have ordered to the East my “Death Head Units” with the order to kill without pity or mercy all men, women and children of Polish race or language’. And even if he had known there was nothing much he, in his position, could have done about it, for the slide into degradation by the political and military forces under the Nazis had already been permitted to pass the point of no return. All the military could do now, apart from an act of outright revolution for which they were neither adjusted nor organised, was mitigate the worst ramifications of evil perpetrated by the monster they had permitted and, at times, welcomed into their midst. Those who have never suffered a situation similar to that in Germany in 1939 are entitled to maintain that the generals should have behaved differently, but they should also view the situation from the generals’ point of view – and ask themselves, too, how many Allied generals, faced with circumstances they did not approve – such as the Bomber Offensive against civilians – made a worthwhile protest?
Predictably Guderian decided that XIX Corps’ main effort should be made by 3rd Panzer Division along his right flank where a deep penetration would benefit from the protection provided by two streams running parallel with the division’s boundaries. That way, too, he would have the satisfaction of quickly capturing the family home of Gross-Klonia. The two motorised divisions were told to enter less promising territory: one rather feels that Guderian attached little importance to their role.
He travelled with the leading tanks of 3rd Panzer Division in one of the latest armoured command vehicles, equipped with radio that enabled speech to his main headquarters in the rear and such other formations as he needed. His account of the first day’s action in Panzer Leader embodies the full fury of the prejudices he had acquired through frustration in the past decade: his anger with the artillery when they fired into the morning mist against orders, bracketing his vehicle and frightening the driver into a ditch: his disgust when he arrived at the Brahe to find stalemate, a complete loss of impetus without a single senior commander in sight to re-inject momentum. In sight of the family home he was enraged to discover that the commander of 6th Panzer Regiment had halted because he thought the river too strongly defended, and that the divisional commander, Generalleutnant Geyr von Schweppenburg, was nowhere to be found. Geyr, by his account, had been called back to Army Group for consultation – a barely credible state of affairs when one realises that his division was entirely fresh to battle and demanding of personal leadership. It took the example set by a young tank commander, who had found a bridge that was undemolished, and by his own intervention in conjunction with the commander of 3rd Rifle Brigade, to get things moving again. Soon infantry, supported by tanks, were across the river at hardly any cost. The main casualty was Schweppenburg’s injured pride: his petulant protests were loudly to be heard, both then and in after years when he complained about Guderian’s interference. Schweppenburg, of course, was a disappointed man and jealous of Guderian, who had overtaken him in the race for promotion. Yet he had little cause for complaint at his treatment on 1st September if he was absent at the crucial moment of decision and had failed to implement his Corps commander’s orders.
Fear of Polish horsed cavalry on the part of his staff and by infantry officers bothered Guderian as he toured the battlefield in his endeavours to overcome the inhibiting fears of troops who were largely inexperienced and under fire for the first time. His disgust at a commander who felt compelled to withdraw at news of the presence of Polish cavalry makes entertaining reading: ‘When I regained the use of my voice I asked the divisional commander if he had ever heard of Pomeranian grenadiers being broken by hostile cavalry.’ There came an assurance that the positions would be held. And in due course it was his personal leadership in the van of the attack which sent the motorised infantry division into an attack towards Tuchel. This, the first twenty-four hours’ experience of combat, was vital to the future self-confidence of the panzer force. Guderian, by his untiring efforts in supervising the establishment of both a technique of command at the front and also his own reputation for fearlessness and undeniable authority, where the fighting was heaviest, made success a certainty. Even if a few senior officers were bruised and disgruntled, the rest of his officers and men were deeply appreciative. All were impressed. It is after 1st September that one begins to detect that look of frank adulation on the faces of soldiers when they were photographed talking to Guderian.
Resistance by the Poles was, in fact, disjointed but usually fierce. The charge by the Pomorska Cavalry Brigade against 3rd Panzer Division’s tanks was but one of many gallant but quite fruitless attempts to redeem disaster. Polish deployment had been wrecked by air attacks upon communication centres. German tanks were exploiting that disruption by almost unchecked advances, blazing away at those enemy columns they caught on the roads, helping infantry and engineers in their assaults upon fortifications, moving cross-country in sweeping, outflanking attacks whenever the natural line of advance was blocked. Always they were on the move and thoroughly self-sufficient within the organisation of the all-arms panzer division; only rarely were they very much assisted by bombing attacks because, primarily, the Luftwaffe was engaged against targets deep in the Polish rear and, secondly, the means of close liaison between ground and air forces was as yet in its infancy. This was not surprising: the Luftwaffe was only luke warm to direct support of the Army. The Air Field Manual No. 16 laid down that ‘The mission of the Luftwaffe is to serve this purpose [the defeat of the enemy military forces as part of a process of breaking the will of the enemy] by conducting air warfare as part of the overall pattern for the conduct of the war’. And Generalleutnant Wolfram von Richthofen, who had experimented with close air support of armies in Spain, and who, in due course, was to make his reputation as the commander of an air force which carried out the most effective and devastating operations by bombers in close support of Guderian’s panzer divisions, was an opponent of the dive-bomber. Such difficulties as 3rd Panzer Division suffered were much more the outcome of failures in equipment and organisation than the result of the enemy’s retaliation. The little Pz I tanks and also the Pz IIs were far too thinly armoured to withstand even the light Polish field artillery and anti-tank gun fire. It was only the handful of Pz III and IV tanks, most of them manned for the sake of experience by the Panzer Demonstration training units, which produced a rare advantage. Supply problems were hampering too. On 2nd September Polish counter-attacks, which cut 3rd Panzer in two on the eastern bank of the Brahe, might have been more quickly contained had the tanks not been stalled for lack of fuel – the supply columns being deprived of adequate orders to send them forward in time to replenish the tanks after the first day of battle. Each inadequacy and breakdown was noted and, whenever possible within existing resources, put right on the spot by Nehring and his staff at Corps HQ or by the divisional and lower staffs when there came a lull in the fighting after the collapse of Polish resistance in the Corridor on 5th September. The bearer of victory was Guderian’s Corps which had sealed off the major Polish formations and made it impossible for them to break the cordon. Thus armoured troops had done all that Guderian claimed for them – broken through in a direct assault, carried out a pursuit and held vital ground under enemy pressure – and they had done these things at that lightning pace which he insisted was essential.
Recounting the first day’s fighting in a letter to Gretel on 4th September he cheered at his successes, mourned the dead and gave credit to the foe. ‘Series losses occurred at Gross-Klonia where a tank company lost one officer, one officer cadet and eight men due to the sudden lifting of the morning mist [despite bombing, the Polish artillery often fought to the end]. At the decisive point I exerted myself personally with success in order to overcome a slight set-back. The 3rd Panzer Division was the first to reach its objective in the night. The others were unable to push back the hard-fighting Poles quite so quickly … though fighting in woodland area with, here and there, heavy losses. With the deployment of a further infantry division and after some crises in heavy fighting, we succeeded in encircling completely the opposing enemy in the woods north of Schwetz to the west. On the 4th the encirclement was tightened. Several thousand prisoners, light and heavy batteries and much material was captured … Lively small skirmishes will continue for a while in the large woods as many scattered troops are still roaming about. The troops fought brilliantly and are in an excellent frame of mind.’ Then followed the names of officers who had fallen and a mention of his delight at meeting their younger son, Kurt, at a point ‘from where one can see the towers of Kulm’, his own birthplace.
Already Gretel had caught the excitement of his mood and on the 5th she had written: ‘I know that my men are the best soldiers. May God send them back to me with Victory – that Germany may live and at last find peace … I am burning to know where and how your troops are victorious… I followed your hard work and strife: now may God give you undisputed success.’
A momentous occasion for Guderian was his opportunity on 5th September to conduct Hitler, Himmler and their entourage round the battlefield – the party shepherded along by an officer who had once commanded the 10th Jägers – Erwin Rommel, in his capacity as Commander of Hitler’s headquarters in the field. For the first time the Führer was given a partial insight into the essentials of modern war. Some of his illusions were shattered, but the educational process was superficial – as time would show. Yet there is vast significance in his question to Guderian concerning the sight of shattered Polish artillery: ‘Our dive-bombers did that?’ and Guderian’s emphatic and proud reply, ‘No! Our panzers!’ At that moment it was faintly born upon Hitler, along with Guderian’s announcement of a mere 150 dead in his entire Corps, that the truly dominant weapon on land might be the tank force. Up to then he had been enslaved by Göring’s claim for the omnipotence of air power. Now he was shown that tanks were an ubiquitous, life-saving weapon and that air-power had its limitations. And the rapid advance of the other armoured formations to the gates of Warsaw and through the mountains in the south told the same story, leaving nobody of balanced judgement in any doubt that, even in unfavourable territory, panzer divisions could make a decisive impression.
But the campaign, though won, was far from over. Next day XIX Corps was sent across the Vistula and transported through East Prussia, close to Bartenstein, to concentrate on the left wing of the German Army as it prepared to drive south towards Brest Litovsk. This provided an opportunity for the Corps Commander to relax while his staff did the donkey work, and it was part of Guderian’s make-up that he could do so – in style. On the night of the 6th he slept in the bed which once had been used by Napoleon in Finkenstein Castle: with amused vanity he relished the privilege. The following night, while his troops drove up for action, he went deer shooting and bagged a large twelve-pointer. Fortunate the staff which has such a trusting commander. Within a few hours he was planning again, receiving his orders from Bock and negotiating for alterations so that his Corps, now strengthened by the substitution of 10th Panzer Division for 2nd Motorised Division, should be left free to make full use of its immense striking power. The initial scheme put forward by OKH to von Bock’s Army Group North on the 4/5th September was anything but productive of wide-ranging, fast panzer attacks. XIX Corps was to be kept in close attendance of Third Army and held back at infantry speed. Moreover the fear of strong intervention by the French in the West (the fact that it had not yet taken place after the Anglo-French declaration of war on 3rd September was the cause of some amazement) deterred OKH from committing major forces too far east when it appreciated that, already, the Poles were broken. Incursions east of a line Ostrow Mazowiecka – Warsaw were forbidden. Bock, whose concept of mobile operations was acute, protested without avail long before Guderian was told of the restrictions and had the chance to add his own vehement objections to Bock on 8th September. But on the 8th it suddenly transpired that Army Group South had not, after all, captured Warsaw: nor had it crossed the Vistula as it had claimed. In fact, 4th Panzer Division had taken a hammering, with the loss of 57 out of 120 tanks, as it tried to break into the city, and there were signs of a major Polish counter-offensive opening along the River Bzura to the west. In these changed circumstances Bock now obtained permission to use XIX Corps to wider and better effect, bringing it under direct command on the left of Third Army and aiming it against Brest Litovsk, far to the east and rear of Warsaw. While Rundstedt and Manstein were preparing for a tactical envelopment on the Bzura, Guderian was given the opportunity he yearned for – a strategic envelopment from north to south with massed panzers.
Already XXI Corps had begun to push across the River Narew against the sternly resisting Polish Narew Group and was aided initially by the presence of 10th Panzer Division. But the moment that division was Withdrawn from command and switched to the left flank where XIX Corps was being pushed through by Guderian, the impetus of XXI Corps’ operations was lost. Here, as elsewhere, infantry unsupported by armour had a rough ride against a determined enemy – and this applied equally to 10th Panzer’s infantry regiment. Last-minute changes of plan also caused confusion in XIX Corps whose inexperienced troops as yet lacked a common method of operation. Moreover unsubstantiated reports by the leading troops, which claimed advances that had not yet taken place, gave a false impression and caused the operation to be launched in a haphazard manner. It was the same in 10th Panzer as it had been with 3rd Panzer on the first day: local commanders were too far to the rear to enable them to both understand and have control over the situation: operations ground to a halt for lack of leadership. While the tanks remained on the home bank of the river, awaiting ferries or the construction of a bridge, the infantry were held up, and not until 1800 hrs on the 9th were a sufficient number of tanks across to join the infantry in an attack which was immediately successful. Guderian was on the spot, urging on the attack and ordering the building of bridges that would carry the tanks next day.
Again there was confusion after he had left the front and returned to his main headquarters for the routine evening exchange of views and orders with Nehring. During the night the commander of 20th Motorised Division, which was under orders to cross the river on the right of 10th Panzer, demanded and received the bridges which Guderian intended for use by the tanks. Progress was made only slowly against extremely stiff resistance from the 18th Polish Infantry Division which had already given XXI Corps a rough handling and now was withdrawing southward. It was 20th Motorised Division’s turn to grapple with 18th Division while the two panzer divisions began their drive towards the River Bug. Immediately the dangers to unarmoured troops in maintaining a deep penetration were exposed. 20th Motorised Division called for help almost at once, and 10th Panzer had to be diverted to their assistance. Meanwhile 3rd Panzer Division, moving into the lead on the left flank, felt itself in danger from the remains of the Narew Group and the Podlaska Cavalry Brigade which lurked on the left flank and rear from the vicinity of Grodno and Bialystok. Guderian ignores this threat in Panzer Leader, but the War Diary (KTB) of XIX Corps does not make light of it. Nehring realised the threat and, moreover, on the night of the 10th/11th was prevented with Main Headquarters from joining Guderian because Polish troops had cut the road. Rightly Guderian admits to moving the headquarters prematurely over the Narew: there was no need since the radio sets were well within range of each other and a headquarter’s effectiveness is reduced each time it makes a move. Furthermore the perils of a roving commander in the forefront of the battle were enunciated at this moment of maximum Polish reaction. That day Guderian himself was cut off and had to be rescued by motor-cyclists, and on the 12th the commander of 2nd Motorised Division, travelling ahead of his formation on reversion to Guderian’s Command, was cut off for several hours by Polish troops. These were the penalties of over-confidence allied to a failure to realise that, within the confines of a grapple when the enemy was present in strength, the major portion of panzer divisions was every bit as vulnerable as other troops and that the comparative safety inherent in vast movement was nullified until conditions of untrammelled mobility had been created.
These conditions were fully satisfied on 13th September when 18th Polish Division surrendered. OKH now took advantage of XIX Corps’ location deep among the enemy in the east to make use of it as a flank guard to the rest of the forces to the westward, and began to reinforce it by XXI Corps against the threat of flank attack from the forests to the east. Complex traffic control problems immediately arose, not only those caused by XIX Corps’ immense train of motor vehicles pouring from north to south along the inadequate road system towards Brest Litovsk, but also in passing XXI Corps’ slower moving, horse drawn transport from west to east across the XIX Corps’ axis. It said much for the system of traffic control which had been devised before the war, and the understanding among the staff, that this operation was actuated with a minimum of confusion. XIX Corps ran free and arrived at Brest Litovsk on the 14th, with its two panzer divisions leading and the motorised divisions echeloned back as flank protection on either wing. Speed was the essence of victory: at Zabinka the sudden arrival of 3rd Panzer Division caught Polish tanks in the act of detraining and destroyed them.