By July 1919, relations between Poland and Lithuania had significantly worsened, despite both sides sharing a common enemy – Soviet Russia. Attempts to solve the border dispute with the Foch Line had failed to solve the issue and the two sides had entered into a short but violent conflict at Sejny. After a ceasefire brought the fighting to a halt, the Lithuanians withdrew to their side of the border. Tensions between the two countries were still high though.

Polish Chief of State Józef Piłsudski secretly plotted to overthrow the Lithuanian government and replace it with a pro-Polish one. Not only would this put an end to the fighting, but it would ensure that Lithuania was receptive to becoming part of the Intermarium – Pilsudski’s scheme to bring Poland, Lithuania, Belarus, Ukraine, and Latvia together as a united federation (the idea was based on a previous Polish-Lithuanian commonwealth that existed from 1569–1795.)

1919 map showing Poland and Lithuania.


The planning started in July 1919, at a time when this part of Europe was in a state of flux. Poland had just signed a ceasefire in the Polish-Ukrainian War; Lithuania had just been invaded by the Bermontians – an army created by Germany but confusingly titled the West Russian Volunteer Army. At the same time, Saxon volunteers were leaving the Lithuanian army.

The Polish Military Organisation had been created by Pilsudski during the First World War primarily for intelligence purposes. Although the Great War had now ended, Pilsudski saw the organisation as an ideal platform to launch a coup d'état.

Pilsudski and Polish Diplomat Leon Wasilewski spent time travelling in the region – both to Vilnius and the Lithuanian temporary capital, Kaunas. They met with various officials, held negotiations and floated the idea of a plebiscite regarding control of the disputed territories (which the Lithuanians rejected, seeing those lands as Lithuanian.)

Although this visit was ostensibly of a peaceful, diplomatic nature, in reality Pilsudski’s real motivations were to assess the likelihood of a coup succeeding, the attitudes of the Lithuanians and whether the PMO were capable of carrying out the plan.

Józef Piłsudski with officers of the Polish Military Organisation (PMO) in 1917.


The Poles planned to present the coup as a popular move amongst the local population as it would free them from German influence.

To this end, the Polish media relentlessly published anti-Lithuanian propaganda, accusing the Lithuanian government of being pro-German and of alleged anti-government sentiments amongst the Lithuanian population. The official goal of the Polish Government was to:

The date is set

The coup was planned for the night of 28/29 August and had the following aims:

  • Capture Kaunas and hold it until the arrival of the Polish regular units invited to protect the city.
  • The Council of Lithuania and the Lithuanian government was to be deposed and replaced by a pro-Polish cabinet.
  • General Silvestras Žukauskas was to be installed as a military dictator of the new Lithuanian government, with Aukštuolaitis as his second-in-command and Narutowicz as the head of the civilian government


General Silvestras Žukauskas

It was anticipated that several high-ranking Lithuanian officials – including General Žukauskas, then chief commander of the Lithuanian forces, would be receptive to the coup due to his friendly attitude towards the Polish. The plotters had been given 800,000 German marks (and were promised another 300,000) to fund the coup.


Unfortunately for the plotters, the Sejny uprising alerted the Lithuanian intelligence services that the Poles were both willing and capable of causing problems for the Lithuanians, particularly as the events at Sejny were started by Poles living in the area but quickly escalated into the Polish miliary – and by extension the government itself – taking an active role. If the Poles were prepared to act in such a manner at Sejny, what else were they prepared to do to undermine Lithuania? Additionally, the Sejny uprising had caused friction within the PMO ranks, with many unhappy it had taken place and feeling it had damaged their reputation.

Poor communication also caused issues for the PMO. They postponed the coup until 1 September, but due to poor communication, some PMO members went ahead and started carrying out acts of sabotage; cutting telephone wires, damaging railways lines etc, which helped alert the Lithuanian intelligence services that something was afoot.


Fearing that the PMO might have even infiltrated the Lithuanian military, a group of Lithuanian officers took the initiative and started rounding up and arresting Polish supporters in Kaunas – over 200 were arrested in total, including 23 Polish Officers who happened to be serving in the Lithuanian army. The PMO themselves escaped detection due to the Lithuanians not being aware of who the members were. They made a second attempt to launch a coup later in September, but this was also discovered and on 21 September, the Lithuanian authorities obtained a full list of PMO members which led to a spate of arrests over the next few days and led to the PMO shutting down their operations in Lithuania.

Lithuanian propaganda leaflet from the 1920s


The Lithuanians charged 117 persons during a military trial on December 11–24, 1920:

  • Six leaders received life sentences.
  • Other sentences ranged from 15 years to 8 months in prison.
  • At least 15 individuals were acquitted.

By 1928 all PMO members had been released by the Lithuanians, some as prisoner exchanges with Lithuanian prisoners or were simply released early. The Polish government initially denied that there was any attempt at a coup but later confirmed that local Poles had planned an uprising, whilst maintaining their own ignorance to it. The Lithuanians remained unconvinced by this explanation, and it further put a strain on Polish–Lithuanian relations.


Pilsudski’s plan was bold but unrealistic. He lacked accurate intelligence and held opinions that were not backed up by facts. There was no evidence to suggest that the Lithuanian government was especially unpopular or that the Lithuanian population were receptive to a Polish takeover – to key factors that would influence the success of the coup.

No high-ranking Lithuanian had indicated support for any such action and the plotters were heavily reliant on the friendliness of General Žukauskas equating to him supporting a coup – yet there was no evidence of this. (Žukauskas himself found his career suffered for his alleged pro-Polish leanings even though there is nothing to suggest he would have supported a coup).

The PMO lacked the organisation and discipline to be able to succeed with such an ambitious plan and were not strong enough to deal with any significant armed opposition they might encounter.



Lesčius, Vytautas (2004). Lietuvos kariuomenė nepriklausomybės kovose 1918–1920 (PDF). Lietuvos kariuomenės istorija (in Lithuanian). Vilnius: General Jonas Žemaitis Military Academy of Lithuania. ISBN 9955-423-23-4. Archived from the original (PDF) on 2011-07-18. Retrieved 2009-08-25.

Łossowski, Piotr (1995). Konflikt polsko-litewski 1918–1920 (in Polish). Książka i Wiedza. ISBN 83-05-12769-9.

Senn, Alfred Erich (1966). The Great Powers, Lithuania and the Vilna Question, 1920–1928. Studies in East European history. Brill Archive. LCC 67086623.

Senn, Alfred Erich (1975) [1959]. The Emergence of Modern Lithuania. Greenwood Press. ISBN 0-8371-7780-4.

(9) Poland and the Baltics - Lithuanian leaflet from the 1920s [1024x728] : MapPorn (