Rinaldo was one of the four sons of Aymon, who married Aya, the
sister of Charlemagne. Thus Rinaldo was nephew to Charlemagne and
cousin of Orlando.

When Rinaldo had grown old enough to assume arms Orlando had won
for himself an illustrious name by his exploits against the
Saracens, whom Charlemagne and his brave knights had driven out of
France. Orlando's fame excited a noble emulation in Rinaldo. Eager
to go in pursuit of glory, he wandered in the country near Paris,
and one day saw at the foot of a tree a superb horse, fully
equipped and loaded with a complete suit of armor. Rinaldo clothed
himself in the armor and mounted the horse, but took not the
sword. On the day when, with his brothers, he had received the
honor of knighthood from the Emperor he had sworn never to bind a
sword to his side till he had wrested one from some famous knight.

Rinaldo took his way to the forest of Arden, celebrated for so
many adventures. Hardly had he entered it when he met an old man,
bending under the weight of years, and learned from him that the
forest was infested with a wild horse, untamable, that broke and
overturned everything that opposed his career. To attack him, he
said, or even to meet him, was certain death. Rinaldo, far from
being alarmed, showed the most eager desire to combat the animal.
This was the horse Bayard, afterward so famous. He had formerly
belonged to Amadis of Gaul. After the death of that hero he had
been held under enchantment by the power of a magician, who
predicted that, when the time came to break the spell, he should
be subdued by a knight of the lineage of Amadis, and not less
brave than he.