At its peak, World War II involved approximately 80 countries and territories spread across the entire globe—and roughly one-fourth of those countries and territories were invaded and at least partially occupied by Germany, the leader of the Axis powers. Utilizing brutal and overwhelming blitzkreig ("lightning war") tactics, German forces spread across Europe with remarkable speed and efficiency, requiring just two years to establish an occupied territory comparable to the empires of ancient Rome, Greece, and Persia.
Countries Invaded by Germany During World War II:
- Czechoslovakia (modern Czech Republic and Slovakia)
- Guernsey (U.K. Channel Island)
- Jersey (U.K. Channel Island)
- Russia (partial occupation)
- San Marino
- Yugoslavia (modern Albania, Croatia, Montenegro, North Macedonia, and Serbia)
Countries Hitler Invaded in World War II (in order):
Austria — March 12, 1938
Germany's annexation of Austria was one of the most unusual invasions of the war: The majority of Austrian people welcomed the Germans into the country, believing the Anchluss (German for "joining") would heal Austria's stagnant economy. The joining of Austria and Germany had been forbidden in the Treaty of Versaille at the end of World War I, but to Germany's Adolf Hitler, Austria was simply an extension of Germany. Most Austrians voted retroactively to approve the measure (although the Jewish and Roma peoples were not allowed to vote) and eagerly joined the Nazi cause.
Czechoslovakia — September 29, 1938
Germany's takeover of Sudetenland—a region of Czechoslovakia that bordered Germany and was populated largely by ethnic Germans—was accomplished almost without bloodshed. Despite France promising to protect Czech territory in 1924 and 1925, France, Italy, and Great Britain in 1938 signed the Munich Agreement, which acquiesced to German demands that Sudetenland be given to Germany. While many Czechs were displeased, the Munich Agreement was widely praised at the time—Hitler had claimed the Sudetenland would be the last of his territorial claims, so the general belief was that the agreement had averted full-scale war in Europe.
For Hitler, the Munich Agreement served two major purposes. First, it validated his bullish tactics, proving he could push other European powers until they backed down without a fight. Secondly, it united the German-speaking people of Czechoslovakia with Germany—another step in his greater goal of uniting all German-speakers into a single nation.
In March 1939, Hitler convinced the Slovak region of Czechoslovakia to declare its independence as the First Slovak Republic (Slovakia), which he immeditately adopted as a Nazi puppet state. Hitler's forces then invaded the remaining Czech territory in clear violation of the Munich Agreement, completing his takeover of the country. In a related development, German ally Italy would invade and annex Albania on April 7, 1939.
Poland — September 01, 1939
Hitler's attack on Germany is often cited as the inflection point that officially launched World War II. Nazi forces charged into Poland from the North, South, and West on September 01 and were joined on September 17 by forces from Russia (which has signed a non-aggression treaty with Germany) attacking from the East. Poland fell swiftly, and on October 06, Russia and Germany divided and annexed the entirety of Polish territory. This gave Hitler's forces more "Lebensraum," or living space, which was in-line with Hitler's belief that the Germans had a right (as the "master race") to occupy a greater territory.
Russia would go on to invade Finland on November 30, 1939.
Denmark and Norway — April 09, 1940
Although a small contingent of German-speakers did make their homes in the country's southern region, Hitler's interest in Denmark was more strategic than ethnic. Overtaking the small country—which surrendered on the day of the initial invasion—helped Germany secure its northern border, and Northern Jutland provided the Nazis an tactically valuable base from which to launch attacks.
Norway's invasion was also strategic rather than ideological and was primarily based on economic reasons. Upon completing its takeover of Norway on June 09, the Germans secured access to North Atlantic trade routes that were vital to Europe, bolstering Germany's trade options while also complicating trade for Great Britain and France. The country also provided access to the mines of Sweden to the east and the south. Both minerals and secure trade routes would be critical for the Germans' war effort.
France, Belgium, Netherlands, Luxembourg — May 10, 1940
Germany turned its attention to Western Europe with an attack on multiple nations at once. Tiny Luxembourg was swiftly overrun by German tanks and surrendered within a day. The Netherlands fell soon after, surrendering on May 14 upon realizing it had no counter for the German Luftwaffe's devastating bombing campaign. Germany's initial push into Belgium was met by resistance from Allied forces who had been preparing for just such an invasion—however, the attack was a feint. The main German force deployed secretly into the Belgian forest, skirted the battle lines and surrounded the defenders, pushing them back toward the waters of the English Channel, resulting in the famous sea-bourne evacuation of more than 300,000 Allied soldiers at Dunkirk, France from May 26 to June 04 and the surrender of Belgium on May 28, 1940.
France (2nd offensive) — June 05, 1940
Hitler then refocused upon taking France, which had helped defeat Germany in World War I and had attacked Germany in September 1939 before retreating. After the First World War, France had constructed a sturdy concrete defense, referred to as the Maginot Line, along its border with Germany. However, France had not extended the Maginot Line along the Belgium border. Although rejuvenated French and British forces put up a valiant fight near the river Somme, additional German forces were able to bypass the Maginot line entirely by cutting through Belgium and entered France's capital of Paris virtually unimpeded on June 14. France signed an armistice with Germany on June 22 and officially surrendered on June 24, 1940. The site of the surrender is Compiègne, France, the same location at which Germany had surrendered at the end of World War I. Part of France then becomes the illegitimate German puppet state Vichy France.
Guernsey and Jersey (British Channel Islands) — June 30, 1940
While these small islands off the coast of Norway did house small airfields, the British government decided not to defend them in event of an attack from Germany. After playing a role in the evacuation of troops from Dunkirk, Belgium (see below), the island's residents were advised to evacuate. Many did, but those who stayed were subjected to occupation when the Germans arrived, took over, and began constructing defenses and (eventually) deporting residents back to Germany. The occupation was also marked by food shortages and fiercer-than-expected resistance from small groups of Channel Islanders.
Greece — April 06, 1941
Although fascist Italy had invaded Greece in October 1940 and again in March 1941 (via Albania), Germany did not join the offensive until April 06, 1941, when Nazi forces pushed into Greece from Bulgaria. The resulting two-front war proved too much for the Greek defenders, and Athens fell on April 27, 1941, followed by the rest of the country by April 30. Greece was then divided up between the Italians (who occupied the bulk of Greek territory), the Bulgarians, and the Germans.
Yugoslavia (modern Albania, Croatia, Montenegro, North Macedonia, and Serbia) — April 06, 1941
Yugoslavia was invaded by the combined might of Germany, Italy, and Hungary following a coup d'état that had overthrown YYugoslavia's Axis-friendly government. The battle was decided quickly, with Yugoslavia surrendering on April 17. A handful of illegitimate German puppet states were established, including the Independent State of Croatia, Nedić's Serbia, and the Kingdom of Montenegro. The remaining Yugoslavian territory was annexed and divided between Germany, Hungary, Italy, Albania, and Bulgaria.
The Soviet Union — June 22, 1941
One of Hitler's most costly strategic decisions was his decision to invade the Soviet Union, which had been an ally of Germany up to that point. However, Hitler opposed the Soviets' communist ideology (as well as its many Jewish citizens), and believed it was part of the Nazis' destiny to repopulate western Russia with Germans. So he violated Germany's non-aggression pact with Russia and launched Operation Barbarossa, establishing the Eastern Front of the war.
By any measure, Operation Barbarossa was massive. The Axis powers sent 3.8 million soldiers into the Soviet Union—more than had participated in any invasion in known history—and fought along a zone of conflict 2,900 kilometers (1,800 miles) long. The battles that ensued were among the largest and deadliest of all time, resulting in millions of casualties not only on the battlefield, but from the deliberate gassing or starvation of prisoners and occupied peoples by the Nazis. Ultimately, however, despite a strong initial push into the Soviet Union, Hitler's forces were defeated. Many historians point to this loss (and the Soviet Union's subsequent joining with the Allies) as one of the major turning points in the war.
Lithuania, Latvia, and Estonia (Soviet territories) — June 22, 1941
Often caught between Germany and the Soviet Union both geographically and politically, the neutral country of Lithuania endured one of the more unique occupations of World War II. Lithuania was one of Hitler's first targets, with the dictator having demanded on 20 March, 1939, that Lithuania give Germany the Klaipėda Region, a disputed territory that had been taken from Germany in the Treaty of Versailles after World War I and was at that time occupied by Lithuania, or risk invasion. The ultimatum was granted, and the Germans took over the Klaipėda Region. However, Lithuania's role in the conflict was far from over.
On June 14, 1940, the Soviet Union (an Axis nation at the time) issued an ultimatum of its own demanding that Lithuania allow the Soviets to establish a puppet government and move troops freely through the country. With little military of its own, Lithuania accepted and was effectively absorbed into the Soviet Union. Latvia and Estonia were given similar ultimatums on June 16 and quickly surrendered.
However, just over a year later on June 22, 1941, Germany declared war on the Soviet Union and invaded Lithuania (and later Latvia and Estonia). The Germans were initially welcomed, even assisted by the Lithuanians, who saw the Nazis pushing out the country's Soviet occupiers. However, the Nazi occupation was much worse and included the execution of roughly 95% of the roughly 210,000 Jews living in Lithuania. The Germans reached Estonia on July 7-9, 1941, and took over Latvia on July 10, 1941, and performed similar purges in both territories. The German occupation would last until Soviet forces recaptured the Baltic states in 1944. After the war, Lithuania, Latvia, and Estonia would be absorbed into the U.S.S.R. until 1990.
Ukraine — June 22, 1941
Ukraine was a founding member of the Soviet Union in 1922. However, the fit was not ideal, and like Lithuanians, many Ukraininans initially welcomed the Nazi invasion of Ukraine, believing German occupation would be preferable to the existing Soviet rule. It was not, as an estimated seven million Ukrainian civilians (including a great many Jews) were slaughtered by Nazi troops. The last Germans would not be repelled from Ukraine until October 1944, an event that Ukraine now celebrates every October 28 as Liberation Day.
Italy — September 08, 1943
Although fascist Italy, led by Benito Mussolini, had been one of Hitler's strongest allies from the start of the war, the situation had changed by 1943. Mussolini had been deposed and on September 03, 1943, Italy signed an armistice with the Allies. This prompted Hitler to invade the former Axis power on September 08, 1943. The offensive was both quick and extremely effective, as German forces were already assembled all throughout Italy as a result of the two countries' previously close alliance. Moreover, Italy's newly non-Mussolini-led government had not yet perfected its strategy or military operations. Upon Hitler's order to attack, the Germans simply turned on the poorly organized Italian forces and made short work of their former allies. Mussolini was installed as a puppet leader in the north and the Allies were left clinging to a small portion of land to the south—though they would reclaim much of the country in the weeks that followed.
Monaco — September 09, 1943
Despite its determination to remain neutral, the tiny state of Monaco was occupied by Italian forces from November 11, 1942, to September 09, 1943, then by German forces from September 09, 1943 to September 03, 1944. Faced with a difficult situation—the country had no military of its own—Monaco's Prince Louis II chose to welcome and cooperate with Monaco's occupiers, which enabled Monaco to escape the war with minimal death and destruction—although the deportation of 90 people, mostly Jews, from "neutral" Monaco to Germany was an act that weighed on the national conscience for generations, and for which Prince Albert II apologized in 2015.
Hungary — March 12, 1944
By 1944, the tide had begun to turn against Hitler. As such, longtime Axis power Hungary had begun negotiating a surrender in secret with the Allied forces. Upon learning of this plan, Hitler sought to prevent Hungary's capitulation. He summoned Hungarian Regent Miklós Horthy to a series of negotiations, leaving the Hungarian army without its commander in chief, and sent troops to overtake the country in the meantime. Hitler then gave Horty an ultimatum to install a Nazi-friendly prime minister, rendering Hungary a German puppet state, or face war with Germany.
San Marino — September 1944
The Italian city-state of San Marino was fortunate enough to remain one of the neutral countries in World War II and escape the majority of the death and destruction. However, German troops did enter San Marino in September 1944 and fought the Battle of San Marino against Allied pursuers from September 17-20. The Germans lost, and order was quickly restored.