Appearing during the Baroque period, the obbligato is an instrumental solo that accompanies the singing part and enrich the continuo in many arias.The clarinet obbligato appears first in the operas by Pasquale Anfossi and Jean Chrétien Bach but also in religious works in the second half of the eighteenth century. It is especially the Italians who will use the clarinet. 

The chamber music obligato becomes very popular in the Romantic era. The most common combinatoin will be the trio with soprano and piano, but a certain number of works call for two mezzos or even a male voice. Germany will be the main country where these works will be written. 

The great romantic virtuosos like Baermann, Cavallini, Crusel, Hermstedt, Klosé and Lazarus will inspire composers and popularize the genre throughout Europe. Before the twentieth century, nearly a hundred composers will have written obbligatos for clarinet. A much larger and diverse repertoire than what is commonly believed, and largely to be rediscovered.