Thinking Medieval: Slings and why they fell out of favor

Slings were effective weapons in warfare for over a millenium of Earth history. The most famous slingers in history were the Balearic Slingers and they were commonly sought as mercenaries for centuries.   Slings have similar range and damage output to crossbows and with a similar if not better rate of fire. Also slings are much cheaper to manufacture and ammunition is practically free.   So why did slings fall out of favor?   Let's look back to what made the Balaeric Slingers so special. Throughout the history of warfare, successful nations copied the best weapons and tactics of their allies and enemies, but neither the Carthagians nor the Romans nor anyone else every made their own home grown version of the Balaeric Slingers.   Children on the Baeleric Islands were pushed to practice with slings extensively from a very young age and continued vigorous through adulthood which is why the Balaerics were experts at using slings, and the slingers that left the islands were the best of the best.   This is why crossbows won out, the learning curve. It takes time and practice to a master a crossbow, but it takes it takes less time than it takes to learn how to use a sling with accuracy and consistency.  

How does this apply to Scarterra?

  Slings would be something elves and humans used when their races were young but it would have fallen out of favor as long bows and crossbows became widely available. Even the remaining nomadic human and elf tribes probably would not use slings much.   But sling use would not disappear entirely. It's a good for a warrior or hunter on a tight budget. It also would be something accessible in a kingdom with strict laws on who can or cannot own a weapon.   Many goblin and kobold tribes would have many skilled slingers, as well as a few other savage humanoids. Igundans are a fairly "young" race but they are certainly smart enough to pick up sling use from watching kobolds and goblins.   Scarterra's various "savage" or "monstrous" mortals certainly have to do a lot of hunting and hit-and-run combat and slings would help them. They certainly have the time and opportunity to push their young to train in slings like the Baelerics of Earth did.  

Staff Slings

  Slings as battlefield weapons mostly disappeared in medieval times but they evolved into a sort of siege weapon known as staff slings.   Staff slings don't have the speed or accuracy of conventional slings but they allow the wielder to lob much larger rocks with very trajectory arcs. They were sometimes used during medieval era sieges and there is no reason they wouldn't sometimes be seen in Scarterran sieges.