The principal foundation sires were Thoroughbred race horses of small stature.

This bull became the foundation sire for the breed.

That price reflected the horse's greatness and his promise as one of the foundation sires in American racing.

He is another foundation sire for the Lipizzan breed.

Sam is considered one of the foundation sires for modern field lines.

There were two primary stallions that are considered foundation sires of the breed.

Quite a few horses had a double cross or were line-bred to this great foundation sire.

Two other stallions also became influential foundation sires of the breed.

Today, two foundation sires of the breed are recognized, both Thoroughbred crosses.

A second foundation sire was recognized in 1991, Harrison Chief.