Mikalojus Radvilaitis

Mikalojus "the Old" Radvila
Born	c. 1450
Died	16 July 1509 (aged 58–59)
Noble family	Radziwiłł
Spouse(s)	Sofija Ona Manvydaitė Zofia Zasławska Fiedora Rohatyńska
Issue with Sofija Ona Manvydaitė: Mikolaj Radziwiłł Jan Radziwiłł Anna Radziwiłł Wojciech Radziwiłł Jerzy Radziwiłł
Father	Radvila Astikas
Mother	Eudoxia Radziwiłł

Mikalojus Radvila or Mikolaj I nicknamed the Old (Lithuanian: Mikalojus Radvilaitis, Mikalojus II Radvila Senasis, Latin: Nicolaus II Radziwil Priscus) (c. 1450 – 16 July 1509) was a Lithuanian noble. 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. His sons Jerzy/Jurgis, Mikojal/Mikalojus and Jan/Jonas were the progenitors of the three Radziwill family lines.