Peter the Hermit
As lieutenant to Peter the Hermit, he co-led the People's Crusade at the beginning of the First Crusade. Leaving well before the main army of knights and their followers (the more famous "Princes' Crusade"), Walter led his small group of knights at the head of a mass of poorly-armed pilgrims through the Holy Roman Empire, the Kingdom of Hungary and the Serbian (Syrmian) and Bulgarian province of the Eastern Roman Empire, traveling separately from Peter. While they passed through Germany and Hungary uneventfully, Walter's followers plundered the Belgrade area, drawing reprisals upon themselves. From here they continued to Constantinople under Byzantine escort.