Römer was born in the Lithuanian city of Vilna, where he spent most of his life. He owned manors in Kriaunos, Antanašė, Bagdoniškis, Daugirdiškiai, Granapolis, and Dembinė. During the French invasion of Russia, he served as the mayor of Vilna from July to September 1812. Between 1817 and 1820 he served as a Marshal of the Szlachta for the Vilna Governorate. He also served as a head of the regional branch of the National Patriotic Society and the "Towarzystwo Szubrawców" literary society (along with Michał Baliński, Leon Borowski, Ignacy Chodźko, Antoni Gorecki, Kazimierz Kontrym, Józef Sękowski, Jędrzej Śniadecki and Tomasz Zan). He was master of Masonic Lodge Diligent Lithuanian ("Uolusis lietuvis") and chairman of the Great Lodge Perfect Unity ("Tobuloji vienybė").