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CHIVALROUS Definition & Meaning - Merriam-Webster

CHIVALROUS Synonyms: 66 Similar and Opposite Words | Merriam-Webster Thesaurus

The adjective "chivalrous" originated in Middle English (1150-1500) around the 14th century from the Old French words chevalier, meaning "knight", and chevalereux, meaning "knightly", and chevalerie ("knighthood" or "horse soldiery").  it's ultimately from the Latin caballus (horse), reflecting the medieval knight's reliance on a horse.  The word's meaning evolved from the literal "pertaining to knights" to the associated virtues of courage, courtesy, and honor, later revived by Romantic writers. 

According to the Oxford English Dictionary (OED), the adjective "chivalrous" was first used in English around 1374 by Geoffrey Chaucer, author of "The Canterbury Tales". 

Examples of "chivalrous" used in a sentence:  
"That doesn't means you can't be brave, strong and chivalrous." 
"Henry was a chivalrous man at heart, and he loved the chance to save me." 
"Now that I know him and he's my husband, he's so chivalrous."
"Oh, so now you're some sort of chivalrous guy again?" 
"You are such an enigma, one minute all cocky and brash, the next formal and chivalrous."  
"He was too chivalrous to abandon his opponent in an apparent extremity." 
"Since it's not very chivalrous to keep referring to him as an Idiot, ASK IDIOT ABOUT HIMSELF."
"In 1799 Scott translated Goethe's play "Götz von Berlichingen mit der eisernen Hand", the tale of a chivalrous medieval German knight." 
 

Being chivalrous in nature would be one of the only things I would want brought back from the olden times.