- 
  
  This is the date range of the Medieval Era
 - 
  
  Reigned from 800AD-814AD as Holy Roman Emperor. Standardized chants in all churches in the Holy Roman Empire. Everything began to be sung the same way from church to church with little variation.
 - 
  
  Musical treatise dating back to the 10th century AD. Attempts to standardized rules of polyphony. Also deals with tetrachords.
 - 
  
  A 1030 Treatise that discusses techniques related to singing and teaching Gregorian Chant. Main innovation was Hexachord system.Includes the Guidonian Hand, parallel and free organum.
 - 
  
  Received visions of works while working in a monastery. Most prolific composer of the Medieval era, along with Machaut. Works include Ordo Virtutum and Scivias.
 - 
  
  Performers originating from the Occitan region of Modern France. Their works were secular, and dealt with topics such as courtly love and chivalry.
 - 
  
  Period producing music designed to resonate well in a large church like the Notre Dame Cathedral. Only known names of composers: Leonin, Perotin. Book of Organum known as Magnus Liber Organi published.
 - 
  
  Treatise written by Franco of Cologne. Suggested duration of note did not require context to be notated. Led to mensural notation
 - 
  
  French composer of the Medieval era. Cantilena Style, continued toubador tradition, one of the first composers to take credit for their work.
 - 
  
  Written by Phillipe de Vitry. Standardized duration notation for notes.
 - 
  
  Landini cadence, Musica Ficta, influenced by French chanson, wrote 140 Ballate.