Career
He was known after a patronym Radvilaitis, made of his father"s name Radvila, which in turn became a family name of his heirs, Radvilos, later Polonised as Radziwiłł. Mikalojus had been a regent of Smolensk from 2 December 1481. In 1483 a 10,000-strong army was summoned by him for protection of Smolensk lands.
He had been the Castellan of Trakai since 31 May 1488 and regent of Novgorodok, later a regent of Bielsk Podlaski.
He was the Voivod of Vilnius since 1492 and the first Grand Chancellor of Lithuania from 1504 until his death in 1509.
