Jan Teska appeared before German courts several times for his national and patriotic activities and eventually received many financial penalties.

During the war years, he kept sending articles about the battles, soldiers' accounts, as well as editorials to the "Dziennik Bydgoski" run by his wife Wincentyna.

The post-war crisis and progressive inflation led the "Dziennik Bydgoski" to financial difficulties: in 1920, the newspaper was transformed into a joint-stock company, Drukarnia Bydgoska SA, with Jan Teska as its editor-in-chief.

The daily paper was a voice of the Polish Christian democracy, but regularly leaned towards the National Democratic movement and Józef Piłsudski's Sanacja.

Wincentyna and Jan made several acquisitions during the interwar: All these ventures were intended for the Teska to create a group of Christian-democratic newspapers: the attempt unfortunately failed.

After the Invasion of Poland in September 1939, Teska left Bydgoszcz: Nazis forces destroyed the building of the editorial office and the printing house of the Dziennik Bydgoski.

In July 1943, Felczak set up a separate group called Stronnictwo Zrywu Narodowy (English: National Rising Party) or "Zryw": Teska became its president.

At the end of WWII, Teska was nominated by the Political Parties Consultation Commission (Polish: Centralna Komisja Porozumiewawcza Stronnictw Demokratycznych) created in November 1944,[7] as a delegate to the Pomeranian Voivodeship National Council: there, he was representing the press and trade unions.

His initial political views were significantly influenced by a group of activists of the bourgeois movement, gathered around the "Orędownik" magazine, where he worked from 1900.

Once editor of the "Dziennik Bydgoski", Jan Teska proclaimed, in line with his thoughts, that the newspaper would be "an outpost of national defense, a new fortification against the flood of Germans".

[2] He addressed his articles to the people, small merchants, craftsmen, workers, peasants and considered Prosperity to be the main driving force of social progress, achieved by the improvement of trade and industry.

Jan Teska was married to Wincentyna, born on 29 September 1888 in Poznań from Wiktoria née Marszały and Wincenty Winiewicz, a worker.

During the First World War, Wincentyna performed the duties of the publishing house's administrator while cooperating with local female writers, Stefania Tuchołkowa and Alina Prus-Krzemińska.

Despite this political position, Wincentyna refused in 1933 the proposal of Cardinal August Hlond, then Primate of Poland, to transform "Dziennik Bydgoski" into an organ of the Polish Catholic Action.

After the death of Jan, Wincentyna no longer participated in the city's social life; in autumn 1955, she moved to her son's, who had been living in the Polish capital since 1953.