Marco Polo

Here, from the Middle East Forum, is an article by Raymond Ibrahim noting that much of what Marco Polo and other medieval travellers wrote about Islam would be denounced today as "Islamophobic."

Polo describes the Saracens as particularly good at excusing any crime, up to and including murder, provided the victim was not a Muslim. He also notes that a Shia Assassin leader preferred to recruit boys aged 12-20; Ibrahim compares this with Osama Bin Laden's preference for 15-25 years old for jihadis and suicide bombers.