Black Horses for the King

This fast-moving historical fantasy by bestselling author Anne McCaffrey traces the beginnings of the British cavalry, as recounted by a boy growing up in exciting and perilous times.
""After his father's death, young Galwyn Varianus is apprenticed to his uncle, who puts the boy to work on the high seas. But horses, not ships, are Galwyn's passion. Luckily, a passenger aboard, Lord Artos (later to rule as the legendary King Arthur), is bound for the great horse fair at Septimania. Risking his life, Galwyn abandons his uncle to serve the gallant leader. Galywn's calming way with horses quickly impresses Lord Artos and his men. But what no one expects is how crucial Galwyn will be to their upcoming battles--as he masters the secrets of the iron shoes that will protect the exotic horses' delicate hooves. . . .