 Born as Zabitis, he changed his name to Polish Niezabitowski (signed in Lithuanian as Nezabitowskas) to appear to be from the Lithuanian nobility.He likely purchased baptismal records from a noble and thus his date of birth is often incorrectly recorded as 1774.From 1786 to 1792, he attended Kražiai College (equivalent to secondary school) and then enrolled into Vilnius University.