November 12, 2006 Bonus Blog
More left-side, right-side mounting theories:

“I was always told the left handed mount was due to sabres (and the like) were on the left side with most people being right handed. this prevented stabbing your self or the horse when mounting.And in my lessons all horses were trained to mount the same .Truth or fiction , thats the way I learned it.”
—Kip Coryea

“The only absolute in history is to remember there are no absolutes. That being said, why did Anglos mount their horses from the left or near side and the Spanish and Plains Indians mount from the right or far side? One answer might be over 2,000 years old. Roman Cavalry wore their swords on the right side, while the Northern Barbarian tribes (Scythians, Alans, Cimmerians, etc.,) tended to wear their sword or arrows suspended from the left side. Mounting a horse with no stirrups required vaulting and getting your weapon caught up in the moment could be problematic. So what has happened was Northern Europeans probably vaulted from the left and Romans from the right. Spain being more heavily influenced by Rome (up to and including today speaking a Romantic Language) and being the first horseman the Plains Tribes encountered the deduction is simple. That and as soon as the first Roman or Scythian noticed that the Nordic and Alpine Europeans were different in this regard, it immediately became "tradition."
—Alan Huffines

So, if the Spanish copied the Romans and mounted on the right, wouldn’t it stand to reason that Mexican vaqueros would likewise, mount from the right. And do they? I can’t think of an example where I’ve seen Mexicans mounting from the right? Did they switch over? Have I just not seen enough Mexicans on horseback?

”Left or right, mounting is such sweet sorrow.”
—Old Cartoonist Saying