Nicholas I (c. 1255 – 25 July 1318) was the natural son of Bohemian king Ottokar II Premysl and his mistress Agnes of Kuenring. In 1269 he became Duke of Opava (at modern day Opava, Czech Republic) and thereby the progenitor of the Silesian cadet branch of the Premyslid dynasty that lasted until 1521.