Over the next few months censorship was abolished, the founding of independent organizations was made possible, policies towards the Church were liberalized, democratic regulations were gradually brought into the party, and the federalization of the State was prepared, declaring equal rights for Slovakia.
The changes in Czechoslovakia in March ’68 awakened the affinity and hope of the Polish society. People counted on the possibility that similar changes would be possible in PRL as well. A popular slogan in the spring of 1968 was ‘all of Poland is waiting for its Dubcek.’ Cheers for Czechoslovakia were heard during demonstrations in Czestochowa, Krakow, Poznan, Warsaw and other places. Furthermore , student protests in Poland enjoyed the good will of the residents of the CSRS (Czechoslovakian Socialist Republic), at many universities Solidarity resolutions were adopted, the press condemned the anti-student and anti-Semitic campaign, and after being sacked, a group of University of Warsaw professors were offered employment at Charles University in Prague.
Meanwhile, the attitude of the PRL authorities was radically different than that of society. Practically from the beginning, Władysław Gomułka was against the Czechoslovakian reforms, as he had expressed during a meeting with Dubcek in February 1968. On 23 March 1968, during a council of communist state leaders in Dresden, Gomułka in effect became the father of the famous ‘Brezhnev doctrine’ regarding the limited sovereignty of the Soviet bloc nations. PZPR leaders consequently promoted the idea of the forceful crushing of the Prague Spring. An internal anti-Czechoslovakian propaganda campaign commenced, exploiting the fears of the alleged German threat as well as the existing prejudice towards Poland’s neighbours. This proved effective, at least in part.
On 21 August 1968, 250,000 soldiers from four of the Warsaw Pact countries (the Soviet Union, Poland, Hungary, Bulgaria, with the logistic support of East Germany) commenced the intervention; their goal was to accomplish a change of leadership in Czechoslovakia and overturn the process of reforms. The invasion met with mass resistance from the Czechs and Slovaks. Polish society also acknowledged it with a universal outcry; it was considered that the involvement of the Polish forces in the intervention meant dishonour to the uniform of a Polish soldier. The many acts of opposition became an expression of protest. Within 64 towns, 143 cases of leaflet distribution were noted, as well as more than 200 signboards recorded in 49 places. Among other things they proclaimed: “Down with aggression to the Czech republic”, “Gomułka get out of Czechoslovakia”, “For your and our freedom”, “Long live our Czech brothers, out with Gomułka”, “Out with Russian tyranny. We are in solidarity with Czechoslovakia. The press is lying”, “Soviet Union get out of Czechoslovakia”, “Countrymen defend the freedom of CSRS”, “Withdraw the LWP [Polish People’s Army] from the CSRS”, “Hands off the Czechs”, “Long live Czechoslovakia”, “Long live Dubcek”, “We want a Polish Dubcek”, “Polish brothers to arms, leave the communist regime, leave colonialism. We will not be one of the Russian republics, long live free Czechoslovakia”, “The Polish nation has nothing to do with the shameful aggression of the USSR and its supporters in the CSRS. Gomułka's clique is an enforced, occupying power and does not represent the will of the Polish nation. We will not allow it to disgrace the glorious rallying cry of our nation – ‘for your freedom and ours’”, “Shame on the Bolsheviks, bandits and their Warsaw lackeys for assaulting heroic Czechoslovakia”, “Long live Czechoslovakia, down with the red Soviet SS men”, “Get the Russian murderers out of Czech”, “Gomułka, we’ll never forgive you for this”. About 130 people were detained because of their opposition to the intervention. There were even isolated cases of young Poles crossing the border in order to take part in the expected battles for the freedom of Czechoslovakia.
The most tragic manifestation of the protest was the self-immolation of Ryszard Siwiec, which took place on 8 September 1968 in the presence of 100,000 people at the 10th Anniversary Stadium in Warsaw, where a harvest festival was taking place with the participation of the highest authorities, headed by Gomułka and Cyrankiewicz. In the middle of the folk ensembles performance, Siwiec scattered protest leaflets against the intervention that he had prepared earlier, doused himself with solvent and set himself on fire shouting “I protest!“ He died four days later in hospital. A letter, which had been taken by the secret police was only received by his wife 25 years later, in it he wrote, “I am dying in order for truth, humanity, freedom not to die – in dying […] I feel more inner peace than ever before in my life.”
The intervention commenced the so-called process of ‘normalization’ in Czechoslovakia, which meant the gradual moving away from the reforms of the Prague spring. The attempt to build ‘socialism with a human face’ had once again showed the true nature of the system.