In the medieval sport of falconry, hawks or falcons were trained to hunt other birds by the noblemen of Europe. Hunters found the females most amenable to training, and so the female bird was lavished with attention. These highly prized birds were known as "noble" falcons. They were also described as de bonne air, or of good disposition.
This popular term used by French sportsmen was, by the 17th century, extended to mean any cultured or well-groomed person.
This phrase, meaning the highest character or rank, alludes to the upper drawer of a bureau or dresser in which jewelry, money, and other valuables are often kept. It was first used in the 19th century to refer to high social standing and importance, and then later to describe merchandise of the highest quality.
SOURCES: 'The Encyclopedia of Word and Phrase Origins,' by Robert Hendrickson; 'Why You Say It,' by Webb Garrison; 'Facts on File: Dictionary of Clichés,' by Christine Ammer; The Oxford English Dictionary.