Bitless bridle

A bitless bridle is a general term describing a wide range of headgear for horses or other animals that controls the animal without using a bit. Direction control may also be via a noseband or cavesson, if one is used. The term hackamore is the most historically accurate word for most common forms of bitless headgear. However, some modern bitless designs of horse headgear lack the heavy noseband of a true hackamore and instead use straps that tighten around a horse's head to apply pressure in various ways. These are often specifically patented and marketed as "bitless bridles," usually referencing a particular type of headgear known as the cross-under, though other designs are sometimes also given similar names.

It is likely that the first domesticated horses were ridden with some type of noseband, made of various materials such as sinew, leather, or rope. However, because the materials used to make gear other than metal bits disintegrates quickly, archaeological evidence of the earliest use of bitless designs has been difficult to find. The earliest artistic evidence of use of some form of bitless bridle was found in illustrations of Synian horsemen, dated approximately 1400 BC. However, domestication of the horse occurred between 4500 and 3500 BC, while earliest evidence of the use of bits, located in two sites of the Botai culture, dates to about 3500-3000 BC. Thus there is a very high probability that some sort of headgear was used to control horses prior to the development of the bit.

Ancient Mesopotamian forms of bitless headgear were refined into the hakma, a design featuring a heavy braided noseband which dates to the reign of Darius in Ancient Persia, approximately 500 BC. It is the predecessor to the modern bosal-style hackamore as well as the French cavesson, particularly the modern longeing cavesson.

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