John I of Opava-Ratibor

John I of Opava-Ratibor (c. 1322–1380/82) was the only son of Nicholas II of Opava by his first wife, Anna of Racibórz, and through her became sole heir of Racibórz in 1365. From 1367 he ruled Opava jointly with his three half-brothers, and the partition of 1377 left him with Racibórz, Krnov and Bruntál.

In 1375 financial difficulties led him to sell Mikołów and Pless to Vladislaus of Opole. In 1361 he married Anna of Żagań, mother of his heir John II the Iron, and died in 1380 or 1382.