German Army (Wehrmacht) in the context of "Fall Rot"

The Sudetendeutsches Freikorps (SFK) (Sudeten German Free Corps, also known as the Freikorps Sudetenland, Freikorps Henlein and Sudetendeutsche Legion) was a paramilitary organization founded on 17 September 1938 in Germany on direct order of Adolf Hitler. The organization was composed mainly of ethnic German citizens of Czechoslovakia with pro-Nazi sympathies who were sheltered, trained and equipped by the German army and who conducted cross-border terrorist operations into Czechoslovak territory from 1938 to 1939. They played an important role in Hitler's successful effort to occupy Czechoslovakia and annex the region known as Sudetenland into the Third Reich under Nazi Germany.

The Sudetendeutsches Freikorps was a successor to Freiwilliger Schutzdienst, also known as Ordnersgruppe, an organization established by the Sudeten German Party in Czechoslovakia unofficially in 1933 and officially on 17 May 1938, following the example of the Sturmabteilung, the original paramilitary wing of the German Nazi Party. Officially registered as a promoter organization, the Freiwilliger Schutzdienst was dissolved on 16 September 1938 by the Czechoslovak authorities due to its implication in many criminal and terrorist activities. Many of its members as well as leadership, wanted for arrest by Czechoslovak authorities, had moved to Germany where they became the basis of the Sudetendeutsches Freikorps, conducting the Freikorps' first cross-border raids into Czechoslovakia only a few hours after its official establishment. Due to the smooth transition between the two organizations, similar membership, Nazi Germany's sponsorship and application of the same tactic of cross-border raids, some authors often do not particularly distinguish between the actions of Ordner (i.e. up to 16 September 1938) and Freikorps (i.e. from 17 September 1938).

The Manstein plan or Case Yellow (German: Fall Gelb; also known after the war as Unternehmen Sichelschnitt a transliteration of the English Operation Sickle Cut), was the war plan of the German armed forces (Wehrmacht) for the Battle of France in 1940. The original invasion plan was an awkward compromise devised by General Franz Halder, the chief of staff of Oberkommando des Heeres (OKH, Army High Command) that satisfied no one. Documents with details of the plan fell into Belgian hands during the Mechelen incident on 10 January 1940 and the plan was revised several times, each giving more emphasis to an attack by Army Group A through the Ardennes, which progressively reduced the offensive by Army Group B through the Low Countries to a diversion.

In the final version of the plan, the main effort of the German invasion was made against the Ardennes, the weakest part of the Allied line, where the defence was left to second-rate French divisions in the Second Army and the Ninth Army, on the assumption that the difficulty of moving masses of men and equipment would give the French plenty of time to send reinforcements if the area was attacked. The Seventh Army, which had been the most powerful part of the French strategic reserve, had been committed to a rush through Belgium to join with the Dutch Army to the north, in the Breda variant of Plan D, the Allied deployment plan.

The invasion of Belgium or Belgian campaign (10–28 May 1940), often referred to within Belgium as the 18 Days' Campaign (French: Campagne des 18 jours; Dutch: Achttiendaagse Veldtocht), formed part of the larger Battle of France, an offensive campaign by Germany during the Second World War. It took place over 18 days in May 1940 and ended with the German occupation of Belgium following the surrender of the Belgian Army.

On 10 May 1940, Germany invaded Luxembourg, the Netherlands, and Belgium under the operational plan Fall Gelb (Case Yellow). The Allied armies attempted to halt the German Army in Belgium, believing it to be the main German thrust. After the French had fully committed the best of the Allied armies to Belgium between 10 and 12 May, the Germans enacted the second phase of their operation, a break-through, or sickle cut, through the Ardennes, and advanced toward the English Channel. The German Army (Heer) reached the Channel after five days, encircling the Allied armies. The Germans gradually reduced the pocket of Allied forces, forcing them back to the sea. The Belgian Army surrendered on 28 May 1940, ending the battle.

The invasion of Yugoslavia, also known as the April War or Operation 25, was a German-led attack on the Kingdom of Yugoslavia by the Axis powers which began on 6 April 1941 during World War II. The order for the invasion was put forward in "Führer Directive No. 25", which Adolf Hitler issued on 27 March 1941, following a Yugoslav coup d'état that overthrew the pro-Axis government.

The invasion commenced with an overwhelming air attack on Belgrade and facilities of the Royal Yugoslav Air Force (VVKJ) by the Luftwaffe (German Air Force) and attacks by German land forces from southwestern Bulgaria. These attacks were followed by German thrusts from Romania, Hungary and the Ostmark (modern-day Austria, then part of Germany). Italian forces were limited to air and artillery attacks until 11 April, when the Italian Army attacked towards Ljubljana (in modern-day Slovenia) and through Istria and Lika and down the Dalmatian coast. On the same day, Hungarian forces entered Yugoslav Bačka and Baranya, but like the Italians they faced practically light resistance. Italians moved into Dalmatia also from Italian-controlled Albania, after repelling an initial Yugoslav attack there.

The German invasion of Greece or Operation Marita (German: Unternehmen Marita), were the attacks on Greece by Italy and Germany during World War II. The Italian invasion in October 1940, which is usually known as the Greco-Italian War, was followed by the German invasion in April 1941. German landings on the island of Crete (May 1941) came after Allied forces had been defeated in mainland Greece. These battles were part of the greater Balkans Campaign of the Axis powers and their associates.

Following the Italian invasion on 28 October 1940, Greece, with British air and material support, repelled the initial Italian attack and a counter-attack in March 1941. When the German invasion, known as Operation Marita, began on 6 April, the bulk of the Greek Army was on the Greek border with Albania, then a vassal of Italy, from which the Italian troops had attacked. German troops invaded from Bulgaria, creating a second front. Greece received a small reinforcement from British, Australian and New Zealand forces in anticipation of the German attack. The Greek army found itself outnumbered in its effort to defend against both Italian and German troops. As a result, the Metaxas defensive line did not receive adequate troop reinforcements and was quickly overrun by the Germans, who then outflanked the Greek forces at the Albanian border, forcing their surrender. British, Australian and New Zealand forces were overwhelmed and forced to retreat, with the ultimate goal of evacuation. For several days, Allied troops played an important part in containing the German advance on the Thermopylae position, allowing ships to be prepared to evacuate the units defending Greece. The German Army reached the capital, Athens, on 27 April and Greece's southern shore on 30 April, capturing 7,000 British, Australian and New Zealand personnel and ending the battle with a decisive victory. The conquest of Greece was completed with the capture of Crete a month later. Following its fall, Greece was occupied by the military forces of Germany, Italy and Bulgaria.

The Kriegsmarine (German pronunciation: [ˈkʁiːksmaˌʁiːnə], lit. 'War Navy') was the navy of Nazi Germany from 1935 to 1945. It superseded the Imperial German Navy of the German Empire (1871–1918) and the inter-war Reichsmarine (1919–1935) of the Weimar Republic. The Kriegsmarine was one of three official branches, along with the Heer and the Luftwaffe, of the Wehrmacht, the German armed forces from 1935 to 1945.

In violation of the Treaty of Versailles, the Kriegsmarine grew rapidly during the German naval rearmament in the 1930s. The 1919 treaty had limited the size of the German navy and prohibited the building of submarines.

The Battle for Caen (June to August 1944) was a military engagement between the British Second Army and the German Panzergruppe West in the Second World War for control of the city of Caen and its vicinity during the Battle of Normandy. Caen is about 9 mi (14 km) inland from the Calvados coast astride the Orne River and Caen Canal, at the junction of several roads and railways. The communication links made it an important operational objective for both sides. Caen and the area to its south are flatter and more open when compared to the bocage country of western Normandy, and Allied air force commanders wanted the area captured quickly in order to construct airfields to base more aircraft in France proper.

The British 3rd Infantry Division was to seize Caen on D-Day or alternatively, dig in short of the city. Caen, Bayeux and Carentan were not captured on D-Day, and the Allies concentrated on linking the beachheads. British and Canadian forces captured the area of Caen north of the Orne during Operation Charnwood (8–9 July), while the suburbs south of the river were captured by the II Canadian Corps during Operation Atlantic (18–20 July). The fighting was mutually costly, and greatly deprived the Germans of the means to reinforce the western part of the invasion front.

The siege of Warsaw in 1939 was fought between the Polish Warsaw Army (Polish: Armia Warszawska, Armia Warszawa) garrisoned and entrenched in Warsaw and the invading German Army.

It began with huge aerial bombardments initiated by the Luftwaffe starting on September 1, 1939 following the German invasion of Poland. Land fighting started on September 8, when the first German armored units reached the Wola district and south-western suburbs of the city. Despite German radio broadcasts claiming to have captured Warsaw, the initial German attack was repelled and soon afterwards Warsaw was placed under siege. The siege lasted until September 28, when the Polish garrison, commanded under General Walerian Czuma, officially capitulated. The following day approximately 140,000 Polish troops left the city and were taken as prisoners of war. On October 1 the Wehrmacht entered Warsaw, which started a period of German occupation that lasted until the devastating Warsaw Uprising and later until January 17, 1945, when the Wehrmacht troops abandoned the city due to the advance of Soviet forces.

The Western Allied invasion of Germany was coordinated by the Western Allies during the final months of hostilities in the European theatre of World War II. In preparation for the Allied invasion of Germany east of the Rhine, a series of offensive operations were designed to seize and capture its east and west banks: Operation Veritable and Operation Grenade in February 1945, and Operation Lumberjack and Operation Undertone in March 1945; these are considered separate from the main invasion operation. The Allied invasion of Germany east of the Rhine started with the Western Allies crossing the river on 22 March 1945 before fanning out and overrunning all of western Germany from the Baltic in the north to the Alpine passes in the south, where they linked up with troops of the U.S. Fifth Army in Italy. Combined with the capture of Berchtesgaden, any hope of Nazi leadership continuing to wage war from a so-called "national redoubt" or escape through the Alps was crushed, shortly followed by unconditional German surrender on 8 May 1945. This is known as the Central Europe Campaign in United States military histories.

By early 1945, events favored the Allied forces in Europe. On the Western Front, the Allies had been fighting in Germany with campaigns against the Siegfried Line since the Battle of Aachen, the Battle of Metz and the Battle of Hürtgen Forest in late 1944 and by January 1945, had pushed the Germans back to their starting points during the Battle of the Bulge. The failure of this offensive exhausted Germany's strategic reserve, leaving it ill-prepared to resist the final Allied campaigns in Europe. Additional losses in the Rhineland further weakened the German Army, leaving shattered remnants of units to defend the east bank of the Rhine. On 7 March, the Allies seized the intact bridge across the Rhine at Remagen, and established a large bridgehead on the river's east bank. During Operation Lumberjack, Operation Plunder and Operation Undertone, German casualties during February–March 1945 are estimated at 400,000 men, including 280,000 men captured as prisoners of war.