Javelins were in fact extremely popular throughout the Ancient Mediterranean world because as a weapon it was incredibly cheap. The Greeks armed themselves as javelinmen or slingers if they could not afford Hoplite equipment; this was standard practice for most societies in this region and time. Javelins are much easier to use than bows, and therefore lowly peasants who are called upon to fight will more easily choose javelins than bows. Thracian mercenaries were considered experts in the use of javelins and corresponding tactics. In Medieval times the javelin was simply not a part of the main military cultures of Europe. Bows were used as the most important missile weapons, though these do not have the penetrative power of a well-thrown javelin; at least they don't require fluid and energetic action by the soldiers who use them. It was primarily the culture of heavy armour and shields that made light-infantry tactics in Europe ineffective.