From The Art and Popular Culture Encyclopedia
"As old as the tension between art music and vulgar music is, it became radical only in high capitalism. In earlier epochs, art music was able to regenerate its material from time to time and enlarge its sphere by recourse to vulgar music. This is seen in medieval polyphony, which drew upon folk songs for its cantus firmi, and also in Mozart, when he combined peep-show cosmology with opera seria and Singspiel."--"On the Social Situation of Music" (1932) by Theodor Adorno
Opera seria (usually called dramma per musica or melodramma serio) is an Italian musical term which refers to the noble and "serious" style of Italian opera that predominated in Europe from the 1710s to circa 1770. The term itself was rarely used at the time and only became common usage once opera seria became unfashionable, and was viewed as a historical genre. The popular rival to opera seria was opera buffa, the 'comic' opera that took its cue from the improvisatory commedia dell'arte.
Italian opera seria (invariably to Italian librettos) was produced not only in Italy but also in Habsburg Austria, England, Saxony and other German states, even in Spain, and other countries. Opera seria was less popular in France, where the national genre of French opera was preferred. Popular composers of opera seria included Alessandro Scarlatti, Johann Adolf Hasse, Leonardo Vinci, Nicola Porpora, George Frideric Handel, and in the second half of the 18th century Tommaso Traetta, Gluck, and Mozart.