Claudio Giovanni Antonio Monteverdi – 29 November 1643) was an Italian composer, gambist, singer, and Catholic priest. Monteverdi is considered a crucial transitional figure between the Renaissance and the Baroque periods of music history. While he worked extensively in the tradition of earlier Renaissance polyphony, such as in his madrigals, he also made great developments in form and melody and began employing the basso continuo technique, distinctive of the Baroque. Monteverdi wrote one of the earliest operas, L'Orfeo, which is the earliest surviving opera still regularly performed.

https://en.wikipedia.org/wiki/Claudio_Monteverdi