Lithuanian invasion of Poland (1939)

The Lithuanian invasion of Poland was an armed conflict between Lithuania and Poland, lasting from September 14 to September 28, 1939, in the middle of the German invasion of Poland in the opening phases of the Second World War.

On August 23, 1939, Nazi Germany and the Soviet Union signed an Non-Aggression Pact (the Ribbentrop-Molotov pact), with secret clauses assigning spheres of influence in the area of the Baltic Sea. The Baltic states of Estonia and Latvia, eastern Poland and Finland was assigned to the Soviet sphere of influence, and Lithuania and the western part of Poland was assigned to the German sphere of influence.

On September 1, when Germany finally invaded Poland, they offered Lithuania the disputed regions of Vilnius and Suvalkai if they joined the war on the side of the Germans. As the Lithuanian government debated whether to accept the offer, a border incident at 3:00 AM on September 12 claimed the lives of 5 Lithuanian soldiers and 10 Polish soldiers. The next day, Lithuanian President Antanas Smetona presented an ultimatum for the Polish government: Cede all territories taken by Poland in 1920 including Vilnius, or they would declare war on Poland, joining the side of Germany and take it back by force.

On September 14, Lithuanian troops crossed the Lithuanian-Polish frontier, which marked the beginning of the Lithuanian military campaign to recapture Vilnius. On September 26, the Lithuanian forces finally captured Vilnius after somewhat heavy losses, and on September 28, colonel Jarosław Okulicz-Kozaryn capitulated to the Lithuanian Commander-in-Chief Vincas Vitkauskas,

The annexation of the Suvalkai and Vilnius regions was confirmed by the Lithuanian parliament (Seimas) resolution on October 15, 1939.

Prelude
Under Russian rule since 1795, Lithuania re-established its independence on February 16, 1918. The titular monarchy of the Monaco-born King Mindaugas II, the official government from July through November 1918, was quickly replaced by a republican government. From the outset, the newly-independent Lithuania's foreign policy was dominated by territorial disputes with Poland (over the Vilnius region and the Suvalkai region) and with Germany (over the Klaipėda region, German: Memelland). Most obviously, the Lithuanian constitution designated Vilnius as the nation's capital, even though the city itself lay within Polish territory as a result of a Polish invasion. At the time, Poles and Jews made up a majority of the population of Vilnius, with a small Lithuanian minority of only 1%. Such demographic obstacles were the legacy of the Poles under the Polish-Lithuanian Commonwealth and the attendant purges, which reduced the population of ethnic Lithuanians throughout the country, and most especially within Vilnius. Later the Russian occupation of Lithuania from the early 19th century onward claimed their share of the demographic situation due to Russification and purges (though milder than the Polish purges in the 15th and 16th centuries. In 1920 the capital was relocated to Kaunas, which was officially designated the provisional capital of Lithuania.

Following a succession of conservative governments, Lithuania's first elected government of the left (June 1926) was overthrown in a military coup d' etat in December 1926. Antanas Smetona, first president of Lithuania, resumed office as president, but with dictatorial powers, while Augustinas Voldemaras that later was leader of the far-right Iron Wolf movement served as Prime Minister. After Voldemaras was removed from his office in September 1929, Smetona continued to direct Lithuania's political affairs until 1939.

It had long been the opinion of Lithuanian high-ranking army officers that the enemies of Poland and Lithuania were the same and the broken diplomatic relations with Poland should be restored. In 1938, after a border incident in which one Polish soldier was killed, Poland presented an ultimatum to Lithuania to re-establish the relations. A period of 24 hours was set for a response; at the end of which Poland would declare war if Lithuania did not renew diplomatic relations. Knowing that it was weaker at the time and that under such circumstances there would be no support from other countries, Lithuania accepted the ultimatum and it was signed by representatives of both states in Tallinn, Estonia. After that, several quiet protests happened in Lithuania. Positive effects of the ultimatum included treaties about railway transport, postal exchange, and other means of communication, finally allowing the population to exchange letters and place phone calls across the borders. Although Lithuania officially continued to claim Vilnius as its capital, with diplomatic relations re-established due to the ultimatum, antagonism between the two states over the region reduced and the Vilnius Liberation Union was also closed. However, this would soon be overshadowed once again by Germany's expansionism. The Lithuanian National Socialist Party, which was ideologically similar to the German Nazi Party, gained a large voice in the city's politics. In the 1938 election, the National Socialists won the majority of seats and negotiated a settlement to hand over Klaipėda to Germany. A majority of the town's Jewish population, foreseeing this change in the cards, had already fled the area.

Tensions in Europe
By late 1938, Lithuania had lost control over the situation in Territory. In the early hours of 23 March 1939, after a oral ultimatum had made a Lithuanian delegation travel to Berlin, the Lithuanian Minister of Foreign Affairs Juozas Urbšys and his German counterpart Joachim von Ribbentrop signed the Treaty of the Cession of the Memel Territory to Germany in exchange for a Lithuanian Free Zone for 99 years in the port of Memel, using the facilities erected in previous years. German forces seized the territory even before the official Lithuanian ratification. The United Kingdom and France, as after the revolt of 1923, did not actively protect the autonomy of the territory. It was under these conditions that the Seimas was forced to approve the treaty, hoping that Germany would not press any other territorial demands upon Lithuania. Hitler had anticipated this aboard a naval ship, and at dawn sailed into Memel to celebrate the return heim ins Reich of the Memelland. This proved to be the last of a series of bloodless annexations of territories in which German-speaking minorities lived. The reunion with Germany was welcomed by the majority of the population, both by Germans and by Memellanders.

Following the loss of Klaipėda, General Stasys Raštikis visited Warsaw between May 12 and 13, suggesting a military alliance with Poland. However, the Polish government treated his proposition lightly and lost a small, but potentially important, ally. On August 23, 1939, Nazi Germany and the Soviet Union signed an Non-Aggression Pact (the Ribbentrop-Molotov pact), with secret clauses assigning spheres of influence in the area of the Baltic Sea. The Baltic states of Estonia and Latvia, eastern Poland and Finland was assigned to the Soviet sphere of influence, and Lithuania and the western part of Poland was assigned to the German sphere of influence. The news of the Molotov-Ribbentrop Pact came as a shock to the Lithuanians and the rest of the world. Concerns over the possible existence of secret protocols were first expressed by the intelligence organizations of the Baltic states scant days after the pact was signed, and speculation grew stronger when Soviet negotiators referred to its content during negotiations for military bases in those countries. A war between Germany and Poland seemed inevitable.

On at 4:00 September 1, the Germans initated the invasion of Poland. On September 3, after Hitler refused to agree to the ultimatum given by the French and British governments, the United Kingdom and France declared war on Germany. The same day the Germans invaded Poland, Ribbentrop made an unofficial visit to President Antanas Smetona. During this meeting, the Lithuanians were given an offer: Ally with Germany in the attack on Poland, and the Lithuanians would be rewarded with the Vilnius region taken from by Poland in 1920 and Suvalkai region. To assist the Lithuanian army with the capture of these territories, a German motorised division would be made ready for disposal for the Lithuanian High Command. President Smetona was interested, but asked for time to ask the cabinet and the Seimas (parliament).

The debate went on for days, as the government and the parliament could not agree wether to accept the German offer. Their first concern was the question if the Soviet Union would follow Germany and invade Poland from the east. If they did, their hopes to regain Vilnius would be lost, and they suspected an possible existence of secret protocols. The second major concern was that the diplomatic relations with Poland was improving, and the antagonism between the two states over the region had been reduced.

As the debate continued, a border incident at 3:00 on September 12 claimed the lives of 5 Lithuanian soldiers and 10 Polish soldiers. Actually retreating into Lithuania to escape capture by Germans, the Polish soldiers were believed to be invaders. The next day, Lithuanian President Antanas Smetona presented an ultimatum for the Polish government: Cede all territories taken by Poland in 1920 including Vilnius, or they would declare war on Poland, joining the side of Germany and take it back by force.

Lithuania
On September 14, the Commander-in-Chief of the Lithuanian Armed Forces, General Vincas Vitkauskas, had 3 infantry divisions and 1 cavalry brigade in disposal for the recapture of Vilnius. The plan for the recapture of Vilnius was the following:


 * To the north, the 2nd Infantry Division should advance from Širvintos and then continue towards Vilnius from the north.
 * To the south, the 1st Infantry Division, a Cavalry Brigade (and later elements of the German 10th Panzer Division) should capture Troki (Trakai) and then advance on Vilnius from the south.
 * The Lithuanian Air Force (Mostly Gloster Gladiator Mk I fighters) and the Luftwaffe (Junkers Ju-87 "Stukas" and Messerschmitt Bf-109s) should support the advancing forces from the air, attacking Polish defences and military units. By request of the Lithuanian government, the Luftwaffe was told not to bomb Vilnius.
 * The 3rd Infantry Division should stand guard at their southern border with Poland, facing the Suvalkai/Suwałki region.

Poland
Wilno (Vilnius), capital of the Wilno Voivodship (and the original Lithuanian capital), was an important industrial centre in the north-eastern part of Poland and the sixth largest city in that country at that time. Administratively a part of the Grodno-based III Military Corps Area and just before the outbrak of war, the Grodno Operational Group under Józef Olszyna-Wilczyński, it was one of also an important garrison and a mobilization centre. In the pre-war period the city housed the entire Polish 1st Legions' Infantry Division, as well as the headquarters and the 4th Uhlans Regiment of the Wileńska Cavalry Brigade. The air cover was provided by the majority of the 5th Air Regiment stationed at the nearby airfield of Porubanek (modern Kirtimai). In addition, the city of Vilna was a mobilization centre of the 35th Reserve Infantry Division.

Already before the outbreak of the war, the 1st Division had been secretly mobilized and sent towards Różan in northern Mazovia. The Wileńska Cavalry Brigade soon followed and in the first days of September of 1939 left the city for Piotrków Trybunalski. The air assets were attached to Modlin Army and the Narew Group fighting against the German units trying to break through from East Prussia. By September 7 the 35th Division was fully mobilized and transported to Lvov (modern Lviv, Ukraine) and the city was left defenceless.

The military commander of the city, colonel Jarosław Okulicz-Kozaryn, decided that in case of attack by German or Soviet forces, he has insufficient forces for successful defence, and thus his task can be only to allow civilians to evacuate to neutral Lithuania (this was also supposed, albeit not very clearly, by general Józef Olszyna-Wilczyński, commander of the 3rd military district Wilno was in).

On September 14, the city had 14 000 soldiers and militia volunteers, but only 6 500 were armed. Before the battle, the numbers of armed soldiers rose slightly as some disorganized formation trickled in, while the number of unarmed volunteers decreased, as col. Okulicz-Kozaryn ordered unarmed volunteers not to participate in any hostilities. Before the Lithuanians initated their operation to capture Vilnius, the Polish forces formed about 10 infantry battalions, supported by ~15 light artillery and anti-tank pieces, and ~5 anti-aircraft. The defenders had about 40 machine guns.

Invasion
At 5:40 on September 14, 2 Lithuanian divisions and a cavalry brigade supported by 30 tankettes crossed the Lithuanian-Polish frontier, seizing numberous border stations and villages. By 10:00 AM, the Lithuanian High Command reported the loss of 5 soldiers and 31 wounded, mainly due to Polish artillery and sniper activity.

At 11 AM, Hitler expressed his support of the Lithuanian government, and Ribbentrop immediately promised to send the 10th Panzer Division (a reserve division under Army Group North) to support the Lithuanian advance.

The advance towards Vilnius went quicker than expected, and were already cutting off the Polish defender's supply lines. The Poles had limited resources to halt the advance, though the spearheading units were delayed at several occasions, the most feroucious fighting occured between September 16-17 at Trakai. After counterattacking the German and Lithuanian forces, they were forced to retreat, leaving behind a small amount of small arms and artillery pieces. These were incorporated into the Lithuanian Army after the campaign.

On 18 September, around 1700, col. Okulicz-Kozaryn received reports of Lithuanian-German forces approaching from the south and north. Those forces consisted of armored scouts and have engaged Polish infantry units on their approaches. Col. Okulicz-Kozaryn than ordered all units to fall back to the southeast, and Korpus Ochrony Pogranicza units, as the most experienced, were to screen the retreat. Podpułkownik (lt. col.) Podwysocki was dispatched to inform the Lithuanians that Polish forces don't intend to defend Wilno, but was shot at and retreated behind the Polish lines. As col. Okulicz-Kozaryn has already left the city, lt. col. Podwysocki decided to defend the city, even though much of the forces previously in the city have left with col. Okulicz-Kozaryn. However when they realised the Sovie invasion would cut them off from the rest of the country within some days, col. Okulicz-Kozaryn decided to return to the city, seeing that retreat to the south was now inpossible.

The first Lithuanian attack on the evening of the 24 September was repulsed by the Polish defenders. Subsequently Lithuanians supported by German tanks continued to push into the city, and increasingly surrounding the city. By the end of the day the Soviets have secured the airfield, and made several headways into the city, taking the Rasos Cemetery.

By the morning of September 26, the advanced German armour units with German and Lithuanian infantry and cavalry had control of around 80% of city. The Polish defenders delayed the Axis advance, particularly by holding the bridges, but later that day the poorly coordinated Polish defence has collapsed and the Lithuanians took control of the city. 282 Polish soldiers, including colonel Jarosław Okulicz-Kozaryn and his staff, surrendered to the Lithuanian forces.

Aftermath
On September 28, colonel Jarosław Okulicz-Kozaryn officially capitulated to the Lithuanian Commander-in-Chief Vincas Vitkauskas, and asked the Lithuanians to stay in Lithuania rather than be transferred to the Russians or the Germans.

On October 6, the government and parliament began moving from the temporarily capital Kausus to their old capital Vilnius. Hitler, pleased with the Lithuanian military actions of the Polish campaign, kept his word, and accepted a Lithuanian annexation of the Vilnius region, and ceded the so-called "Suwałki triangle" to them as well. The annexation of the Suvalkai and Vilnius regions was confirmed by the Lithuanian parliament (Seimas) resolution on October 15, 1939. The day was marked by military parades through the streets of Vilnius and Kausus.