How did the fugue become established as a complete composition in the Baroque era?

The fugue evolved into a complete, self-contained composition during the Baroque era through a gradual transition from earlier, closely imitative forms. While the term fuga was used for canonic pieces as early as the 14th century, the fugue’s logical ancestors were the imitative beginnings of late 16th-century ensemble canzonas and the ricercare.1

During the 17th century, composers such as Girolamo Frescobaldi and Johann Jakob Froberger began utilizing fugal techniques within larger movements. By the time of Johann Sebastian Bach, the fugue was firmly established as a distinct, self-contained composition or a clearly defined section of a larger work. This development was solidified by the keyboard works of composers like Dietrich Buxtehude, Johann Pachelbel, and Georg Muffat, as well as the orchestral concerti of Antonio Vivaldi. Works such as Johann Caspar Ferdinand Fischer’s Ariadne musica (1702), which paired preludes and fugues in various keys, served as direct forerunners to Bach’s influential The Well-Tempered Clavier.1