After graduating from trade schools in Lubań and Radom, Tomasz Arciszewski moved to Sosnowiec, an ever-growing centre of heavy industry of the region of Zagłębie.

[1] Initially active in Zagłębie, he had to flee the country and between 1898 and 1900 he lived in London and Bremen, where he was one of the leaders of the Association of Polish Socialists in Exile.

After the action of Bezdany he had to flee the Privislinsky Krai and settled in Lwów (now Lviv, Ukraine), where he joined the Association of Active Struggle, a secret para-military organization.

After the Act of 5 November and the proclamation of the Kingdom of Poland as part of the Central Powers' plan of Mitteleuropa, Tomasz Arciszewski entered the city council of Warsaw.

After the collapse of Germany and Austria-Hungary at the end of World War I, on 7 November 1918 Arciszewski was appointed the minister of labour and social affairs in the Provisional Government of the Polish Republic led by Ignacy Daszyński.

After the German and Soviet take-over of Poland he went underground and, together with Kazimierz Pużak, on 16 October of the same year he proclaimed the Polish Socialist Party – Freedom, Equality, Independence (PPS-WRN), a secret war-time continuation of the pre-war PPS.

After that he entered the Council of National Unity (RJN), a quasi-parliament of the Polish Secret State headed by Jan Stanisław Jankowski.

Critical towards the pressure of the Soviet Union and Stanisław Mikołajczyk's attempts at compromise with Joseph Stalin, Arciszewski focused on trying to convince the Allied leaders (notably Winston Churchill) to help fighting Warsaw – to little avail.