 He was made the Rector of the High School of Orsha in 1782 and took part in the Regional Congregation of 1782 and 1785 that elected successively Cerniewicz and Lenkiewicz, Temporary Vicar in Russia.After 1785, Kareu was made Rector of the most prestigious Jesuit College in Russia, Polatsk.In this period, he funded the purchase of a printing press from which, school manuals, philosophical and theological treatises and devotional books were produced.