The September Campaign began on September 1, 1939, with Germany's attack on Poland, and on September 17, the Soviet Union joined the invasion. Despite heroic defense, including the symbolic defense of Westerplatte, the military superiority of the aggressors led to Poland's defeat. The campaign ended on October 6, 1939, with the capitulation of the last regular units at Kock.

The September Campaign, which began on September 1, 1939, represents one of the most dramatic chapters in Polish history. It was then that German forces crossed the country's borders, beginning World War II. This event forever changed the course of history not only for Poland but for the entire world.

Despite the heroic defense of Polish soldiers, the September Campaign ended in Poland's defeat. However, the exact date of its end raises some controversy among historians. In this article, we will examine various interpretations and historical facts that shed light on when the September Campaign can actually be considered to have ended.

The September Campaign began on September 1, 1939, at 4:45 AM, when German forces crossed Poland's borders. This moment marked the beginning of World War II and a dramatic period in Polish history.

The German invasion of Poland, known as Fall Weiss (Case White), was a carefully planned military operation. German forces numbered 1.8 million soldiers, 2,800 tanks, and 2,000 aircraft. The attack came from three directions: East Prussia, Pomerania, and Silesia. German troops employed Blitzkrieg tactics (lightning war), combining rapid strikes by armored units with air attacks.

Great Britain and France, being Poland's allies, declared war on Germany on September 3, 1939. Despite the formal declaration of war, the allies did not undertake significant military actions in support of Poland. The French conducted a limited offensive in the Saar Basin, which did not bring the expected results. The British limited themselves to dropping propaganda leaflets over German territory. This passive stance of the allies went down in history as the "Phoney War."

The September Campaign was characterized by intensive military operations on Polish territory. The German offensive, based on the Blitzkrieg strategy, quickly broke through Polish defenses, leading to a series of key battles and engagements.

The September Campaign was rich in significant battles that determined Poland's fate. The Battle of Bzura (September 9-22, 1939) was the largest engagement of the campaign, where Polish forces attempted a counteroffensive. The Battle of Mława (September 1-4, 1939) delayed the German attack on Warsaw. The Defense of Wizna (September 7-10, 1939), known as the "Polish Thermopylae," demonstrated the heroism of Polish soldiers. The Battle of Mokra (September 1, 1939) showed the effectiveness of Polish cavalry against German tanks. The Defense of Warsaw (September 8-28, 1939) became a symbol of Polish resistance and determination.

The Defense of Westerplatte became a symbol of Polish resistance during the September Campaign. On September 1, 1939, at 4:45 AM, the German battleship Schleswig-Holstein began shelling the Polish military outpost at Westerplatte. 182 Polish soldiers under the command of Major Henryk Sucharski faced over 3,000 German attackers. For seven days, the defenders of Westerplatte repelled German attacks with limited armament and supplies. The heroic stance of Polish soldiers at Westerplatte became an inspiration for the entire nation and a symbol of the fight for independence.

Poland's political and military situation in September 1939 was extremely difficult. The country found itself facing a powerful enemy with significant numerical and technological superiority.

The Polish army numbered about 950,000 soldiers, 4,300 artillery pieces, 880 tanks, and 400 combat aircraft. Polish military doctrine assumed the defense of the entire border, which dispersed forces and hindered effective defense. Plan "Z" (West) anticipated holding back the German offensive until Western allies could intervene.

Key elements of Polish defense:

• Establishing defense lines along major rivers: Narew, Vistula, and San
• Mobilization of reservists and volunteers
• Attempts to modernize military equipment, including production of new 7TP tank models

However, Polish command underestimated the scale and pace of the German attack, which contributed to the rapid collapse of defensive lines.

On September 17, 1939, faced with the Soviet invasion from the east, the Polish government and High Command decided to evacuate. Key events:

• President Ignacy Mościcki crossed the Romanian border on September 17 at 21:45
• Commander-in-Chief Edward Śmigły-Rydz left the country on September 18 at 6:30
• The Polish government was interned in Romania

The evacuation of state authorities had serious consequences:

1. Disorganization of command structure
2. Decline in morale among soldiers and civilians
3. Hindrance to coordination of defensive operations

Despite the evacuation, Polish diplomatic missions abroad continued their activities, trying to obtain international aid and maintain the continuity of the Polish state in the international arena.

On September 17, 1939, the Red Army crossed Poland's eastern border, implementing the secret provisions of the Ribbentrop-Molotov Pact. The Soviet invasion dealt another blow to defending Poland and sealed its fate in the September Campaign.

The Ribbentrop-Molotov Pact, signed on August 23, 1939, contained a secret protocol dividing spheres of influence in Central and Eastern Europe. This document sealed Poland's fate by dividing its territory between Nazi Germany and the Soviet Union. The consequences of the pact for Poland were catastrophic:

• Political isolation of Poland on the international stage
• Inability to effectively defend on two fronts
• Loss of significant eastern territories
• Mass repression against Polish population in territories occupied by the USSR

The pact enabled Stalin to realize his imperial ambitions, leading to the annexation of eastern territories of the Second Polish Republic.

The Red Army's invasion on September 17, 1939, meant Poland had to fight on two fronts:

• Soviet forces: 620,000 soldiers, 4,700 tanks, 3,300 aircraft
• Directions of attack: Belarus, Polesie, Volhynia, Podolia
• Polish resistance: Border Protection Corps, local military units

The two-front aggression led to:

1. Rapid collapse of Polish defense in the east
2. Cutting off evacuation routes for Polish troops
3. Disorganization of Polish command
4. Decline in morale among soldiers and civilians

Coordinated German-Soviet actions accelerated Poland's defeat in the September Campaign. On September 28, 1939, the German-Soviet Boundary and Friendship Treaty was signed, formally dividing Polish territory between the aggressors.

The September Campaign entered its decisive phase in late September 1939. The last days of Poland's defensive war were characterized by heroic resistance in the face of overwhelming enemy forces and key events that sealed the country's fate.

Warsaw, the capital of Poland, fiercely resisted the German invaders for 20 days. The defense of the city lasted from September 8 to September 28, 1939. General Walerian Czuma commanded the city's defense. Despite the heroic stance of the defenders and civilians, the situation in the city became increasingly difficult. Continuous bombardment, lack of food and water, and massive casualties in both human lives and infrastructure forced the defenders to make the decision to surrender. On September 28, 1939, the act of Warsaw's capitulation was signed, marking the symbolic end of organized resistance by the Polish army.

The Battle of Kock was the last major clash of the September Campaign. It lasted from October 2 to October 5, 1939. The Independent Operational Group "Polesie" under General Franciszek Kleeberg's command engaged German armored and motorized units. Polish soldiers, despite exhaustion and lack of supplies, put up fierce resistance. The battle ended with the surrender of Polish forces on October 6, 1939. General Kleeberg, seeing the hopelessness of the situation and wanting to spare his soldiers' lives, made the decision to lay down arms. The Battle of Kock is considered the final chord of the September Campaign and the symbolic end of regular military operations in Poland in 1939.

The official end of the September Campaign remains a topic of discussion among historians. Although most regular military operations ceased in early October, the precise date of the campaign's end is not clearly defined.

The last organized units of the Polish army surrendered on October 6, 1939. On this day, Gen. Franciszek Kleeberg surrendered the Independent Operational Group "Polesie" after the Battle of Kock. This battle, lasting from October 2 to October 5, was the last major clash of the September Campaign. The capitulation of the Independent Operational Group "Polesie" represented the symbolic end of regular military operations in Poland in 1939.

October 6, 1939, is considered by many historians as the official end date of the September Campaign. This date holds special significance because:

1. It marks the end of organized resistance by regular Polish Army units
2. It concludes the period of major military operations in the territory of the Second Polish Republic
3. It symbolizes the transition from open warfare to occupation and partisan activities
4. It serves as a temporal boundary for historical research on the September Campaign

It's worth noting that despite the capitulation of the last regular units, partisan warfare and resistance movements continued. Furthermore, Polish armed forces continued fighting on other fronts of World War II, contributing to the final victory over the Third Reich.

The September Campaign had far-reaching consequences for Poland and its inhabitants. The defeat of Polish forces led to the occupation of the country by Germany and the Soviet Union, initiating a long period of suffering and struggle for the Polish nation.

Poland's territory was divided between Germany and the Soviet Union according to the secret protocol of the Ribbentrop-Molotov Pact. Germany annexed the western and central areas of Poland, creating the General Government. The Soviet Union occupied the eastern provinces, incorporating them into the Belarusian and Ukrainian SSR. This division resulted in:

• Loss of 48% of pre-war Poland's territory to the USSR
• Annexation of 45% of territory by Germany
• Creation of the General Government in the remaining 7% of territory

The defeat in the September Campaign had tragic consequences for Polish soldiers and civilians:

• 66,000 Polish soldiers were killed and 133,700 were wounded
• About 420,000 soldiers were taken into German captivity
• 250,000 soldiers were interned by the Soviets
• Thousands of civilians died as a result of bombings and fighting

The occupiers conducted a policy of terror and extermination:

• Mass executions of intelligentsia and social elites
• Deportations for forced labor to Germany
• Displacement from territories incorporated into the Reich
• Creation of ghettos for Jewish population

Many Poles were forced to flee the country:

• The Polish Government-in-exile continued its activities in London

• Thousands of soldiers evacuated to Romania and Hungary

• Polish Armed Forces in the West were established

• Structures of the Polish Underground State were created

• Resistance movement and underground activities developed

• The Home Army became the largest underground army in occupied Europe

• The September Campaign began on September 1, 1939, with Germany's attack on Poland, which started World War II.
• On September 17, 1939, the Soviet Union attacked Poland from the east, implementing secret provisions of the Ribbentrop-Molotov Pact.
• The capitulation of Warsaw on September 28, 1939, symbolized the end of organized resistance by the Polish army.
• The last major battle of the campaign - at Kock - ended on October 5, and the surrender of Independent Operational Group "Polesie" took place on October 6, 1939.
• The official end of the September Campaign is dated October 6, 1939, although some historians cite different dates.
• The campaign resulted in the division of Polish territory between Germany and the USSR, and the beginning of occupation that lasted until 1945.

The September Campaign of 1939 was a pivotal moment in the history of Poland and Europe. Despite the heroic stance of Polish soldiers, the military superiority of the aggressors proved too great.

The end of the campaign has no definitive date. Most historians consider October 6, 1939, as the symbolic end of the fighting, although resistance continued for much longer.

The consequences of the campaign were tragic for Poland. The country lost its independence and millions of citizens experienced occupation and repression. However, the spirit of resistance survived, creating the foundation for the continued fight for freedom.