An attack on an armed individual carries a considerable element of risk. Therefore it follows that he was attacked for a reason. Most likely something he was carrying. I seriously doubt that he was travelling alone. One, possibly more companion is more likely. Wife, Brother, close relative, member of his tribe.

Its unusual for lone travelers to be attacked. Unless your a member of a tribe at feud/war with another tribe. You are more likely to be welcomed. If only for the news and infomation you have. They might want to trade with your people later. And showing hospitality is a good way to open the door.