Answer :

The thing that happened sometime between 700 and 900, that led to the development of polyphony in western music was Gregorian chant began to have a second melodic line added by monks in monastery choirs.

What was Gregorian chant?

  • The Roman Catholic Church's monophonic, unaccompanied holy song in Latin (and rarely Greek) has its roots in Gregorian chant, which is the main Western plainchant tradition.
  • With later additions and redactions, Gregorian chant evolved mostly in western and central Europe during the ninth and tenth centuries.
  • Although the Gregorian chant is said to have been created by Pope Gregory I, academics think that it was a later Carolingian blend of Roman and Gallican chant.
  • Gregorian chants were initially divided into four modes, then eight, then twelve, and finally.
  • A characteristic ambitus, characteristic intervallic patterns in relation to the final of a referential mode, incipits and cadences, and the usage of reciting tones at a specific distance from the final are all examples of typical melodic elements.

To learn more about Gregorian chant refer to:

https://brainly.com/question/1285864

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