Łódź insurrection ( 1905 ) The Łódź insurrection , also known as the June Days , was an uprising by Polish workers in Łódź against the Russian Empire between 21 – 25 June 1905 . This event was one of the largest disturbances in the Russian - controlled Congress Poland during the Russian Revolution of 1905 . Poland was a major center of revolutionary fighting in the Russian Empire in 1905 – 1907 , and the Łódź insurrection was a key incident in those events . For months , workers in Łódź had been in a state of unrest , with several major strikes having taken place , which were forcibly suppressed by the Russian police and military . The insurrection began spontaneously , without backing from any organized group . Polish revolutionary groups were taken by surprise and did not play a major role in the subsequent events . Around 21 – 22 June , following clashes with the authorities in the previous days , angry workers began building barricades and assaulting police and military patrols . Additional troops were called by the authorities , who also declared martial law . On 23 June , no businesses operated in the city , as the police and military stormed dozens of workers ' barricades . Eventually , by 25 June , the uprising was crushed , with estimates of several hundred dead and wounded . The uprising was reported in the international press and widely discussed by socialist and communist activists worldwide . Unrest in Łódź would continue for many months , although without protests on such a large - scale as before . Background . At the beginning of the 20th century , worsening economic conditions contributed to mounting tensions in Russia and Poland : the Russo - Japanese War had damaged the economy of the Kingdom of Poland , and by late 1904 , over 100 , 000 Polish workers had lost their jobs . In the late 19th and early 20th centuries , Łódź had been a major Polish industrial center , heavily urbanized and industrialized , and its large working class made it an important stronghold of the Polish socialist movement . News of the 1905 Russian revolution , together with its revolutionary spirit , spread quickly into Russian - controlled Poland from Saint Petersburg , where demonstrators had been massacred on 22 January . Poland was a major center of revolutionary fighting in the Russian Empire in 1905 – 1907 , and the Łódź insurrection was a key incident in those events . Workers in Łódź had already begun striking sometime before 22 January , and by 31 January the tsarist police were reporting demonstrators carrying placards with slogans such as " Down with the autocracy ! Down with the war ! " . This was capitalized on by factions in Russia and Poland that wanted more or less radical changes . Soon over 400 , 000 workers became involved in strikes in Poland . The wing of the Polish Socialist Party ( " Polska Partia Socjalistyczna , PPS " ) that was loyal to Józef Piłsudski believed that Poles should show their determination to regain independence through active , violent protests against the Russians . This view was not shared by Roman Dmowski ' s National Democratic Party ( ND , ) nor by the PPS ' s own " Left " ( or " Young " ) wing . The National Democrats favored cooperation with the Russian authorities , while the PPS Left wanted to work together with Russian revolutionaries to topple the tsardom and saw the creation of a socialist utopia as more important than Polish independence . The Russo - Japanese War had caused rising dissent throughout the Russian Empire , including its Polish provinces . On 26 January 1905 about 6 , 000 workers in Łódź took part in a large strike . Next day , a general strike was declared , and the day after that , 70 , 000 workers were on strike . They demanded an 8 - hour work day and support for the sick . Some worker demonstrations were joined by the students , who demanded an end to the policy of Russification . Another large strike occurred during the Labor Day on 1 May . It affected close to half of the city ' s industry . On 3 May , the anniversary of the Polish May Constitution , another demonstration with patriotic undertones took place . On 30 May , Łódź ' s industrialists asked the Russian governor - general for help . The murder of the worker Jerzy Grabczyński by Russian Cossack cavalry at the Grohmana is mentioned as one of the sparks of the insurrection . On 18 June 1905 , Russian police opened fire on one of the many workers ' demonstrations in Łódź , killing approximately ten workers , whose funerals , attended by over 50 , 000 – 70 , 000 people , escalated into major demonstrations on 20 and 21 June . The funeral on 21 June was met by Cossack cavalry again ; the crowd threw stones , and the Russian cavalry returned fire , killing 25 people and wounding hundreds . Social Democracy of the Kingdom of Poland and Lithuania ( SDKPiL ) called for a general strike on 23 June . Piłsudski ' s PPS , while not planning for a major uprising then and there , had a policy of supporting the protest and harassing Russian forces . The PPS , as well as other socialist organizations , such as Jewish Bund and SDKPiL , were as surprised by the scale of the spontaneous revolt as the Russian authorities ; PPS forces in Łódź consisted of 10 regular and armed PPS members and a few dozen semi - enlisted workers . A larger group sent from Warsaw under Walery Sławek never made it in time to take control or affect the uprising ; it was , in the end , an anarchic and unorganized violent protest against the Russian government . Uprising . Tensions mounted further , and in the evening of 21 or 22 June ( sources vary ) , angry workers began building barricades and assaulting police and military patrols , killing those who did not surrender . About a hundred barricades were constructed over the course of the next few days . Around Wschodnia street , workers opened fire on a company of soldiers and cavalry , and on Południowa street , a unit of gendarmes was surrounded . Several fires begun in the town , as workers set liquor stores on fire , and the government forces assaulted the first barricades , initially without much success . The tsarist representatives called from reinforcements , which came from Częstochowa , Warsaw , and summer training camps . Several infantry regiment s entered the city . Eventually , Russian forces sent to suppress the workers numbered six infantry regiments and several cavalry regiments . Despite that , the situation was spiralling into a full blown uprising . On 23 June , all industries , workshops , shops and offices were closed , as the workers and government forces clashed . Some of the heaviest fighting took place near the intersection of Wschodnia and Południowa ( now Rewolucji 1905 r . ) streets ( where four barricades were located ) , near the Scheibler factory in the Źródliska park and on the Rokociny road ( al . Piłsudskiego ) . The Rokociny area was manned by a 3 , 000 - strong worker militia , which eventually was forced to retreat to the Źródliska park . The insurgents had no organized agenda , and commonly fought under red standards ; common demands were the improvement of workers ' living conditions and greater rights for the Polish population . On 23 June ( or as late as 26 June – sources vary ) the Tsar signed a decree of martial law in the city . The PPS - supported worker factions found themselves facing not only Russian police and regular troops , but " endecja " militia . Armed clashes broke out between gunmen loyal to Piłsudski ' s PPS and those loyal to Dmowski . Over the course of the " June Days " , as the Łódź uprising became known in Poland , a miniature civil war raged between Piłsudski ' s PPS and Dmowski ' s " endeks . " The insurgents were poorly armed , and eventually were overwhelmed by the tsarist regular military . Most of the barricades fell by 24 June ; the last of the barricade s ( in the Źródliska park and Wschodnia street ) were captured by Russian troops by the end of 24 June or by midday on 25 June ( sources vary ) , but unrest — including occasional shots at police or military patrols — would continue for days afterwards . Aftermath . The uprising was ultimately crushed by the Russian authorities . Official reports indicated 151 civilian deaths ( 55 Poles , 79 Jews and 17 Germans ) and 150 wounded ; unofficial reports spoke of over 200 fatalities and between 800 and as many as 2 , 000 wounded . The Łódź uprising was neither the first nor the last disturbance in what has been described in Polish historiography as the revolution in the Kingdom of Poland ( 1905 – 1907 ) — various protests and strikes occurred in major Polish cities under Russian control throughout the year — but it would be the most dramatic one . In September 1905 , two PPS activists would assassinate Juliusz Karol Kunitzer , owner of the Heinzel & Kunitzer factory , known for his poor treatment of workers . Strikes in Łódź continued until mid - 1906 , when the large Russian military presence and mass layoffs of striking workers from the factories finally pacified the city . Even afterward , Łódź was not a peaceful city ; in the years 1910 – 1914 it was the site of a radical , anarchist and socialist group Rewolucyjni Mściciele labeled as " the most extreme , terrorist group in the history of Poland " . The uprising was reported in the international press and recognized by socialist and communist activists worldwide . Notes . a Sources are not in universal agreement as to when the insurrection started and ended . Many sources give dates of 22 – 24 June ; however , according to some sources , the police and military were attacked as early as 21 June , and the final barricade fell on 25 June .