] ] Great horses are very large horses originally bred, I believe, to carry a knight in his heavy steel armour. We know them as "shire" horses or Belgians.

During the Mad Cow scare, I heard a very interesting explanation of why roast beef is so popular in England. During the Crusades, all the big horses were used by knights, and farmers kept oxen for plowing (okay, ploughing) and such. When the flower of knighthood faded away, these big horses were available for use as farm animals, and the oxen found their way to the dinner table.

Not being a farmer, I do not know whether it is easier to drive a team of horses or a team of oxen, but as horses are still used, I guess they are better at the job.