The First Crusade Part Two By: Mike Bond | - It should be remembered that at this time, 1095, when Urban was preaching the Crusade, or more accurately, the Pilgrimage; the name 'Crusade' didn't appear until many years later, the knights were merely men who rode horses into battle.
They could be employed as farmers of a nobleman's lands, freemen, who were expected to drop everything and fight for their liegelord if the need arose.