History
In 1519 Spanish explorer Hernando Cortes sailed to America to try and make his fortune. When he got here he notices these horses that were “dark roan” with “white patches”. By the early 1800s these horses roamed the Plains. They were favored by the Comanche Indians, who were considered to be the best Indian horsemen. The first breed association for these horses, the Pinto Horse Association, was formed in the late 1950s.
Origin
No one knows how early these horses originated, but they were roaming America when Cortes was here in 1519. They were very popular among Plains Indians.
Physical Characteristics
Paint horses have a well muscled build and usually they have a distinct coat color. Many times their body shapes resemble the American Quarter Horse. Most range from 14.2 to 16hh, but there is no height requirement. They can be any color and have white patches any where on their body. Depending on where those patches fall decides what coat pattern that horse has.
Solid: No white patches: 
Tobiano: Solid colored horse with 4 at least partially colored legs, the white usually crosses the spine and are rounded shapes, possibly a “normally” marked face, and often a two colored tail:
Overo: Irregular head markings, the white marks are more splashy and usually do not cross the spine, between 1 and 4 dark legs, and usually a single colored tail: 
Tovero: Any combination of Tobiano and Overo coat patters, different sized spots, dark skin around ears, eyes, and mouth, at least one blue eye: 
Links
The American Paint Horse Association is a great place to learn more information.
