Oldest Surviving Saddle

• The oldest surviving saddle was found on the back of a mummified horse in Pazryrk, Siberia. It is thought to date back to 3000 BC.
  
  

First Saddle Tree

• The oldest saddles were merely pads attached to a girth. The next step in the evolution seems to be the invention of sturdier saddles with padding over a solid wooden frame (tree). According to The Ultimate Horse Book, saddle trees were invented by the Sarmatians about 300 AD.
  
  

First Riders

• It is now thought the first horseback riders were in what is now Khazikstan, 2,000 years before domestication in Europe ("Horses first ridden and milked 5500 years ago" by Ben Hirshler, Reuters, March 5, 2009). They used bridles, but whether or not they used saddles is still unknown.
  
  

First Western Saddle

• Modern Western saddle. Image from Wikimedia Commons.
  
  The modern Western (cowboy) saddle did not appear until the early 1800s. It evolved in Mexico from Spanish cavalry saddles of the 1700s.
  
  

Fun Fact

• The stirrup was not included in the designs for the earliest saddles. The Encyclopaedia Britannica claims that the stirrup was invented in 200 BC in Asia, most likely in the Asian steppes.