Some suggestions of names for horses from A New Method and Extraordinary Invention to dress Horses, And work them according to Nature; As also, to perfect NATURE by the Subtilty of ART; Which was never found out, but by the Thrice Noble, High and puissant PRINCE William Cavendishe (1657):
Bonissimo
Grandissimo
La Petite Barbe
L’Amour
Mala Testa
Gatto
(Cavendish was perhaps the most influential of the Brits who tried to import the Continental Haut Ecole style, although it was never very popular with a nation who preferred to hunt and race than passage and piaffe.)