I agree, a Mexican Charro or Spanish Bull Fighting type saddle. It looks like a good quality, hand-made saddle. If so, I'd say it's worth something like $800-2,500, depending on the quality and brand, if any.
I would clean it with a soft toothbrush and Lexol cleaner
or castile soap (available at the grocery store or drug store, in the laundry isle). Use very small circular motions with the toothbrush to lift out the dirt and grime. Rinse with warm water and wipe clean, let dry. Clean again if there is still more dirt. Keep cleaning, GENTLY, until it all lifts up. Do NOT scrub the leather with a sponge or the toothbrush. You can ruin the finish of the leather and strip the color.
Use some baking soda with water (to make a paste) for the white sections and metal. Store it on a barrel or saddle rack with LOTS of blankets on it, to help spread the skirts and packs back out.
Use Passier Lederbalsam
on all of the leather, both sides. If it soaks it all in by the next day, put on another coat. Apply it using your hands, to warm it and help it soak in to the leather. Passier's conditioner is really good for leather, won't weaken it or the stitching, and after it's dry you can buff it to a nice glow (use a soft cloth or sheepskin/fleece scrap).