Bonawentura Niemojowski was born in Słupia near Kępno to a noble (szlachta) family (Wierusz Coat of Arms).
[1] One of the demands of the Kalisz faction in 1820, regarding independence of the judiciary, led the tsar Alexander I of Russia (who was also king of Congress Poland, the Russian Empire puppet state) to suspend the Polish parliament for a period of five years; Niemojowski was dismissed from the parliament before that and subject to house arrest for over a year.
[2] Although opposed to any means of revolutionary changes,[3] the Kaliszanie eventually supported the November Uprising and joined the ranks of the National Government in 1830.
During the period of struggle against Russia, the Kaliszanie practically dominated the government, controlling the ministries of internal affairs, treasury and war.
He resigned his post on 23 September, once the majority of the government decided to support capitulation, and was succeeded by general Maciej Rybiński.