The Cavalry class is one of the many new additions in Battlefield 1, and it sounds very exciting.
Just like the dedicated vehicle class, spawning on a horse in Battlefield 1 means you're going to play as a unique class, the Calvary.
This is the first time we've seen a rideable animal in a Battlefield game, and it's also the first time we had dedicated "vehicle" classes. Being a unique class means your loadout on horseback will be different to your actual class loadout.
As you can see in Alex's video above, your main attack weapons are a one-handed rifle and a scimitar. You can only use one at a time, but you also get an anti-vehicle grenade and have the ability to drop ammo/bandages from the saddlebags.
The scimitar allows you to get one-hit kills on soldiers, regardless of the angle. The rifle is a bit weak, but it seems relatively accurate. You can switch between the sword and rifle at any time, but you'll have to go into a bit of a prolonged animations.
It all seems pretty fun, even if it makes you a very big target. You'll be able to try it our for yourself when the beta opens its doors on Wednesday.