[4] During World War II he escaped forced labour for the Germans by taking employment as a gardener and joined the Armia Krajowa (Home Army),[3] the Polish resistance movement.

[5] Siwiec planned his self-immolation months in advance, writing out a last will in April, and leaving written and tape-recorded statements explaining his revulsion at both the Warsaw Pact invasion of Czechoslovakia and the Polish People's Republic's participation in it.

[10] He had a banner with the words "For our freedom and yours" and "Honour, Fatherland" as well as some leaflets, which he is said to have thrown around right before the incident, though neither attracted much attention, and both items are primarily mentioned only in the documents of the investigating secret police.

[10] He retained consciousness after the flames had been extinguished, giving brief statements, as well as later when he was transferred to a hospital (Szpital Praski), where he was able to communicate with the medical personnel, and where he received a brief visit from his wife.

[5] A story invented on the spot was that it was an accident caused by drinking vodka and smoking, or spontaneously combusting, aiming to divert interest to gossip and portray Siwiec as an irresponsible drunk.

[5] There was some gossip about the incident, with most people considering it a suicide rather than an accident, but the reason for it was unclear, and no one connected Siwiec's dramatic actions to contemporary political events.

This changed only after the famous self-immolation of Palach in Prague four months later, on 19 January 1969,[5] and after RFE received more information, which clarified the political statement that Siwiec wanted to make.

[4][6] After the fall of communism, Siwiec became the subject of the 1991 documentary film Hear My Cry (Usłyszcie mój krzyk), by Polish director Maciej Drygas.

[5] Jan Nowak-Jeziorański, the director of the Polish section of Radio Free Europe, expressed a similar sentiment: "This was an unheard of human tragedy...

"[6] In the same vein, Kavaliauskas interprets Drygas' movie as a critique of contemporary Polish society, saying that witnesses did not want to have this incident spoil their enjoyment of the festival on an otherwise "perfect day".

[4] A bridge in Przemyśl, where he lived, was named after him in 1991,[6] as well as a street in Prague in front of the Czech Institute for the Study of Totalitarian Regimes, with a nearby memorial dedicated to him, unveiled in 2010.