During numerous trials he documented typical personalities of the poorer, less-known part of the city with its distinctive culture, language and customs.

They gained much popularity and in late 1930s Wiechecki opened a chocolate shop in the borough of Praga, which became his main source of income.

Sharing the fate of the rest of Warsaw's civilians, Wiechecki was forced out of the city after the end of the uprising.

One of the scientists to defend him in numerous articles was Bronisław Wieczorkiewicz, who later published the first monograph on the dialects of Warsaw.

After 1989 one of the main pedestrian-only zones of downtown Warsaw was officially named the Wiech Passage in honour of Wiechecki.