Fortress Europe- European Fortifications Of World War II

by J E Kaufmann

  WEAPONS AND EQUIPMENT

  WORLD WAR II

  The German battleship Schleszuig-Holstein fired the first salvo of the war by opening fire on the Military Transit Depot at Westerplatte in Danzig (Gdansk). The Poles riposted with two 37-mm guns, a 75-mm gun and small arms from the five sentry-post bunkers. After seven days of determined combat, isolated, without hope of reinforcement, its ammunition depleted, the 182 man garrison surrendered on September 7. In the Hel Peninsula, the Polish forces determinedly repelled all German attacks from land, sea, and air. Forty-six German aircraft were shot down and a destroyer damaged. The small units of the Polish fleet that had remained behind when the few destroyers and submarines escaped to Great Britain, took part in the defense. The German forces, blocked by field obstacles, was unable to reach the Jastarnia defensive point. The Hel Fortified Region did not surrender until October 2, 1939, when its garrison ran out of ammunition, food, and medical supplies.

  In 1939 the Polish Army had virtually given up its effort to defend its eastern territories as the German threat loomed in the west. It rushed instead to complete the fortifications in the areas most threatened by the Germans. The units originally earmarked for Baranowicze, Wolyn, and Polesie in the east were integrated into the Modlin, Pomorze, and Krakow Armies in the west. Thus when the war broke out, the eastern fortified border sectors did not take part in the action, except in a few isolated places.

  On the OWS, engagements with the Germans began a few days prior to the invasion, when bands of Freikorps, sent to create a diversion and gather intelligence, stumbled into the Polish fortifications by accident and exchanged fire with the garrisons. When the war officially started, the Germans avoided the OWS, leaving the Freikorps to operate in the area. Nonetheless, the OWS line managed to hold up the conquest of Upper Silesia for three whole days.

  The Wizna Position, strengthened by troops from Operation Group Narew, included elements from field fortress units. The crews of this position consisted of 720 men, who fought from September 7 to 9 against the German 10th Panzer Division and the Fortress Brigade Lotzen, which they held up for two days until Heinz Guderian's panzer group entered the battle. The commander of the position, Captain W. Raginis, refusing to accept surrender, committed suicide by blowing himself up in the command bunker.

  Early in the campaign the Poznan Army became isolated. The 26th Infantry Division abandoned the Golancz Position without a fight on the night of September 3-4 because other events left it exposed on a flank. The 25th Infantry Division also evacuated the Prosna River Line Position without a fight.

  Further to the south, the Krakow Army was engaged by the 5th Panzer Division, which advanced through the area south of Pszczyna in the direction of the village of Goczalkowice where the schrony were still in the initial stage of construction. The 6th Infantry Division was forced to abandon the defenses on the Pszczyna Position to the north that it had put into service.

  Near the former Czech border, at Wegierska Gorka, in the Beskidy Mountains on the Sola River, a 4 km long position blocked the pass. It included five schrony, four of which were on the valley walls and mounted 37-mm or 75-mm guns. A command post was located among the schrony, near the river. None of these positions (twelve were planned) were fully completed. The troops had to set up their machine guns on sandbags in the wells intended for cloches on the casemates mounting the two 75-mm guns. The garrison, which included members of the 151st Fortress Company and a company from the National Guard Battalion Zywiec, fought fiercely under the command of Captain Tadeusz Semik. It surrendered on September 3, in the face of German air strikes and flamethrower attacks. Thus Hungarian Hill became known as "The Westerplatte of the South."

  On the Warta Line, the Germans engaged the 10th Infantry Division on September 4. By midnight of September 15, after bloody encounters with the German Eighth Army, the Poles withdrew towards Szadek-Lutomiersk.

  The Pomorze Army in the Polish Corridor was overwhelmed by the German Fourth Army and Guderian's attached panzer group early in the campaign. The Koronow Lake Position was abandoned without a struggle when the Germans attacked the interval separating it from the neighboring Drozdzenica-Piastoszyn Position.

  The 20th Infantry Division of the Modlin Army effectively defended the Mlawa Position for three days, after which it abandoned the fortifications on the order of the Commander in Chief of the Armed Forces to avoid being surrounded. In this area both the complete and incomplete casemates of the line had been occupied and put to use, giving the Germans the impression that they had come across a formidable obstacle.

  In his entry dated September 1, 1939, German historian General Nikolaus von Vormann wrote that: "to the north of Mlawa the corps ran into a known enemy fortified position defended on both sides by swamps, and it was not able to break through, despite the use of tanks and Stukas. The units of the corps withdrew, having sustained heavy losses."

  The Germans would again engage troops of the Modlin Army at the old forts of Modlin, which were not taken until the end of the campaign. In fact, the town of Modlin was one of the last to surrender.

  Polish Fortified Group in Black Silesia. An artillery casemate on Hill 310 at Bobrowniki for 2 x 75-mm guns and which each have two embrasures so they can fire in two directions and 2 MGs. Walls up to 1.5 meters. Note observation cloche in center. (Kaufmann)

  Guns of He[ coast defense. The arrow points to one of the coastal defense guns of Hel in 1939. The gun to the right of it was a 120-mm Bofors gun mounted on a minelayer that defended the harbor. The other guns are post-war Soviet weapons used at Hel. (Kaufmann)

  Mlawa Position. This line of fortifications consisted of small casemates like this one which had firing chambers on one or both sides and the entrance to the rear. The concrete had not completely set on most when the war began. The wooden frame which had not yet been removed can still be seen around the embrasure. (Kaufmann)

  Polish Fortified Group. Observation cloche on another position of the group on Hill 310 at Bobrowniki. (Kaufmann)

  Polish heavy bunker of Wedrowiec built on Hungarian Hill Position in Western Beskidy Mountains in summer of 1939.

  Polish heavy bunker in Silesia nearTapkowice built in summer of 1939.

  Polish heavy bunker in Silesia near Laziska built in 1939. One of 10 positions built with garage for AT gun.

  Chapter 11

  YUGOSLAVIA

  BACKGROUND

  Created as the Kingdom of the Serbs, Croats, and Slovenes at the end of the Great War, this nation of Southern Slavs proved to be a hotbed of trouble in one of the most backward parts of Europe. In 1929, Yugoslavia included approximately 4 million Serbs, 2.7 million Croats, 1.4 million Slovenes, and about 4 million members of other ethnic groups teetering on the brink of civil war.' At that time the government changed and the country was renamed Yugoslavia.

  Known as the Kingdom of Illyria and a haven for pirates in Roman times, the Yugoslav kingdom had been for centuries an arena for the struggle between Turks and Europeans. It was also the target of Hungarian and Venetian expansion. Most of its major defenses before World War I had been built to protect the ports of the Dalmatian Coast.

  Soon after attaining independence, Yugoslavia lost Fiume to a paramilitary force led by Italian nationalist Gabriele d'Annunzio in 1919. The Treaty of Rapallo of 1920 made the city a free port, but Italy maintained de facto control. The treaty also allowed Italy to take control of the port of Zara and several Adriatic and coastal islands. Yugoslavia could do little to prevent this, especially since it was preoccupied with Hungarian ambitions. In 1921 Yugoslavia, Rumania, and Czechoslovakia created the Little Entente with the aim of containing Hungary, their common foe. France, who promoted the entente, offered military advice to Czechoslovakia and Yugoslavia. However, in the 1930s only Czechoslovakia was able to take advantage of France's technological support because it had the required industrial base. Yugoslavia, which had an agrarian economy, could not make the most of France's offer. Fortunately for Yugoslavia, its two
hostile neighbors were located on its northwestern and northern border so that its defensive efforts could be concentrated in that direction and along the coast.

  MAJOR FORTIFICATIONS

  Italian Front

  German Front

  Hungarian Front

  Coastal Defenses

  LOCATION

  Yugoslavia's topography was favorable to defense because the country was large and mountainous. Its most productive agricultural region was located on the Pannonian Plain, in Croatia, and northern Serbia. The Danube and two of its tributaries, the Sava and Drava, which drained this area, formed part of the defenses against Hungary. Spring runoff swelled these rivers so much that they became as wide as the Mississippi for weeks. The Danube served as a major transportation artery not only for Yugoslavia, but for most of Central Europe.

  Belgrade, on the Danube, lay at the edge of the Pannonian Plain and the Samadija region, a very hilly and easily defended section of central Serbia. The southern part of Serbia was the mountainous Kosovo region crossed by the Morava River, another tributary of the Danube, and the Vardar River, which flowed into the Aegean. Both rivers formed a corridor into Greece called the Morava-Vardar Depression, one of the most important land routes from northern to southern Yugoslavia. The region was easily defended against Bulgaria and Greece.

  The Dinaric Alps, a part of the Eastern Alpine system, were the nation's highest and most rugged mountains. At average altitudes of 2,500 meters above sea level, they were not as high as the Western Alps but still presented a major obstacle for a modern army. The coastal range fell off steeply into the Adriatic, creating many islands and a rough coastline with deep harbors. Other ranges of the Dinaric Alps sloped eastward into the Karst Plateau, which formed a large part of the country. Forests covered most of the less fertile regions. The cavernous limestone formations of the plateau literally swallowed up many rivers and streams and resembled, in many respects, the Carro Plateau in northeastern Italy, offering the defender all the advantages.

  1. The Italian Front

  Yugoslavia's border with Italy extended for about 290 km. The Julian Alps commanded the main front, aiding in the defense. The easily defended karst topography dominated the region. The front was divided into five sectors. The 2nd sector began at Susak, on the coast and ran northward, to the vicinity of Cabar. The 5th Sector began at Cabar and followed the border to the vicinity of Rakek. The 1st sector stretched between Rakek and Vrhnka, protecting the main road from Ljubljana to Trieste. The 3rd Sector continued on to Skofjalloka, covering Ljubljana. The 4th Sector extended northward to the vicinity of Bohinjska Bistrica and there turned eastward to Trzicz. These defenses occupied Slovenia and protected Ljubljana and Zabreg, separated by the Sava River and dominated by mountains.

  2. The German (former Austrian) Front

  The border with the German Reich was almost totally dominated by the Alps, cut by only a couple of passes and the Mura River valley. The 6th Sector covered this area from Dravograd to the Mura. Only the Mura and Drava valleys could be considered major invasion routes, but the rivers and the rugged terrain were serious obstacles.

  3. The Hungarian Front

  The Drava River formed part of the boundary between Yugoslavia and Hungary. To the south, the Kalnik Mountains, the Bilo Gora Range, and the Papuk Range constituted a major obstacle. On the Hungarian side of the border, the hilly and mountainous Barany region protected the Drava River between the Austrian border and Valpovov. The 7th Sector began at Valpovov and covered the gap between the Drava and Danube Rivers. The 9th Sector extended from the Danube along the Hungarian border to the Rumanian border. The 10th Sector, located to the rear of the 9th sector, stretched between the Danube, near Batina where the 9th Sector began, along the King Peter Canal to the Tisa River. The 10th Sector was the only one located behind another sector. The reason for the concentration of defenses in this area was that it was part of the Great Hungarian Plain that covered most of Hungary east of the Danube and offered the most direct route to Belgrade, the economic and industrial heart of Yugoslavia.

  4. Coastal Defenses

  Yugoslavia had to defend a number of islands that protected the entrances to the bays of the main ports such as Kotor (Cattaro), Dubrovnik, Sibenik, and Split. The islands at Korcula and Zara, whose mountainous terrain gave the defender all the advantages, were among the most important to be fortified. Yugoslav positions ringed the Italian enclave at Zara.

  HISTORY

  The Little Entente proved to be an inadequate check on Hungary after it allied itself to Fascist Italy. In response, Yugoslavia created fortification staffs charged with the development of defenses in an individual area. The first staff was set up at Ljubljana, which was threatened by Italy.

  However, it was not until the 1930s that Yugoslavia made a serious effort to defend its borders. In the mid-1930s, the situation in Central Europe became increasingly precarious as Hitler and Mussolini confronted each other for the first time in 1934 and later embraced each other as allies. As Germany openly violated the Versailles Treaty, the Western Powers vacillated and continued building their own fortifications to ward off German aggression. Eastern Europe was vulnerable since Czechoslovakia and Poland could not settle their differences and present a common front to the growing threat. The Little Entente teetered on the verge of collapse.

  In 1937, faced with such an uncertain future, Yugoslavia caught the fortification building fever that was sweeping Europe. In January 1937, at the suggestion of French military advisers, a Yugoslav army commission went to Czechoslovakia to study methods of fortification.

  Between 1935 and 1939, twelve fortress staffs numbering 15,000 men, went into operation. Five were stationed on the Italian border, one on the Austrian border, and six on the Hungarian border. Additional staffs handled the coastal defenses. Before the war broke out, these staffs grew to over 40,000 men. By 1941, they had erected twelve heavy positions and 4,000 concrete emplacements of various sizes. Yugoslav troops were assigned the task of building defenses after the invasion of Poland. The army called up reservists for several weeks of training, turning them into a construction labor force.

  The numbering of the various defensive sectors appears to indicate their priority. The most important fortifications went up west of Ljubljana while the next most important sector was the 2nd Sector at Susak, also facing Italy. Only limited work was done on the border region of Hungary until early in 1939, a year after the annexation of Austria to the Reich. After the German occupation of the rump of Czechoslovakia, Yugoslavia redoubled its efforts, particularly since it felt increasingly isolated. Rumania had proved a poor ally for Czechoslovakia during the 1938 crisis, and by 1939 Yugoslavia had no allies or neighbors it could rely on.

  Yugoslavia also attempted to fortify the border region with Hungary, fearing that the Germans would violate its territory on their way to an attack on Rumania. In addition, Hungary could not be trusted not to annex the area with a large concentration of ethnic Hungarians. Thus Yugoslavia hastily threw up field fortifications in the last months of 1939.

  In 1939, the Yugoslavs set up four defensive lines between the Tisa and Danube rivers. The first stretched along the border and included anti-tank obstacles, and the second between Sombor and Senta, which became strong points with trenches between them. The King Peter Canal served as an 18 meter wide anti-tank obstacle for the third line. The fourth line had the strongest positions and a number of bridgehead positions at key towns were established.

  According to an American observer, the terrain between the first and fourth lines was not adequate for defensive positions against a modern army. Other American intelligence reports revealed that a number of the Yugoslav casemates and blockhouses reflected a definite French influence.

  Like most of the other nations, Yugoslavia placed its faith in anti-tank obstacles. Some of the permanent fortifications observed in the fall of 1939 were concrete machine gun and anti-tank bunkers while other positions also included underground works
. Casemates for 105-mm weapons and some heavy bunkers were completed in the vicinity of Trata, but they were not armed yet.

  In the 6th Sector, the only significant work was at Maribor. Here, an outpost line was placed on the Mura River, a main line behind the Drava River, and the bridgeheads at Putj and Maribor on the north side of the river. The Yugoslav army relied heavily on the natural obstacles here and in most other sectors. Between the 4th and 6th Sectors was the Austrian front where an outpost line was placed in the Alps to block the Drava Valley near Dravograd, the Seeberg Pass (1218 meters), the Libel Pass (1310 meters), and the Sava Valley. The work on the former Austrian frontier did not begin until the spring of 1939 for fear of German retaliation. The main fortifications were of light and medium type.

  The only permanent works completed in any significant number were on the Italian front in the 1st to the 5th Sectors. Reportedly, a French engineer officer had directed the work since 1938. Before 1936 the Yugoslavs ran their positions along crest lines as a result of lack of experience. After the Yugoslav engineers visited the Czech fortifications the plans were changed, and with the aid of French engineers, the new defenses were sighted on forward slopes with the crests used only for observation posts and assembly positions for counter-attacks.

  On the Italian Front where the Yugoslavs expended their greatest effort, they found that they did not have the finances or time to create a truly modern position. They had prepared plans for the construction of several French-style ouvrages, but changed them to more modest positions with fewer combat blocks. The design of the planned forts shows that the Yugoslavs apparently received technical advice from the Czechs for creating more economical positions. Roads in this area were improved and widened to help the defenders.