Guy of Blois was a medieval nobleman who lived during the 12th century. He was the son of Stephen of Blois, who became King of England. Guy is best known for his role in the First Crusade, where he participated in the siege of Jerusalem in 1099. After the crusade, Guy became the Count of Boulogne and was involved in various conflicts in France and England. His lineage and connections to the royal family influenced the political landscape of the time, as he was part of the ongoing struggles for power between different noble houses.