What Does It Mean to “Be Knighted”?

In Jane Austen’s Pride and Prejudice, Sir William Lucas has been knighted by the King for his service as to Meryton. But what exactly does it mean to be knighted?

David I of Scotland knighting a squire
Unknown – http://manuscriptminiatures.com/3913/14012/ ~ Public Domain

Knighthoods likely date back to ancient Rome. At that time there existed an order of mounted nobles referred to as Ordo Equestris. Knights became the standard of military excellence in European countries. Each “knight” practiced a strict military training from the time he was but a youth. He often learned his trade by serving as an “esquire” to a knight during war years. He would be expected to embrace the strictures of chivalry: generosity, bravery, self-denial, fighting skills, and faithfulness. He would also be expected to maintain the expenses of his trade: arms, armor, horses, assistants, etc., as well to provide followers who would also take…