He was born on 5 April 1784 in a noble family in Słupia near Wieluń. He attended school in Warsaw and then studied in Germany (in Erlangen and Halle). During his stay in France, he became conversant with Benjamin Constant’s doctrine, which in time became his own political philosophy. After Tsar Alexander I had granted an octroyed constitution to the Kingdom of Poland, Niemojowski became involved in political activities. He founded the Reading Society and gathered around himself a group of social and political activists, who were described as the “Kalisz Opposition” owing to the fact that the leading representatives of the group owned estates around Kalisz. His political activity, which was aimed primarily at preserving the liberal provisions of the constitution, was opposed by the authorities of the Kingdom of Poland. From 1820 to 1825, he was excluded from parliamentary activity, and was under house arrest from 1825 to 1830. After the outbreak of the November Uprising, he sat on subsequent insurgent governments. In 1831, he was arrested by the Russians, later tried and sentenced to exile. He died in December 1834 on his way to Siberia. His most important works included: Głosy posła kaliskiego na sejmie Królestwa Polskiego 1818 [“Speeches by the deputy from Kalisz in the Sejm of the Kingdom of Poland”] (1818); Myśli dorywcze o romantykach i romantyczności [“Casual thoughts on romantics and romanticism”] (1830).