William IV of Montferrat

William IV (c. 1030–1100) of the Aleramici dynasty was Marquis of Montferrat from 1084, the eldest son of Marquis Otto II and Constance of Savoy. He first appears in a 1059 document at Savona, where he limited his powers over the city, probably at the citizens’ request.

In 1093 he attended Emperor Henry IV’s donation of the monastery of Breme to the church of Pavia. His successor Rainier was born of his second wife, Otta di Aglié, and William died in 1100.