[1] The town was founded on December 16, 1832, following Governor Juan Manuel de Rosas' orders for the construction of a fort, San Serapio Mártir del Arroyo Azul, to guard against indigenous raids.

Subsequent land grants led to the development of a stable community, and in 1895, Azul was formally declared a town by provincial authorities.

The town's cemetery portal and main slaughterhouse were both designed by architect Francisco Salamone, and contain elements of Art Deco style.

The town was the scene of an attack on outlying Army barracks by far-left ERP militants on January 19, 1974, the most violent assault of its kind in the country up to that point.

[2] The Miguel de Cervantes Festival is held there every spring since 2007, and Casa Ronco, an antiquarian library and museum, maintains the country's best collections relating to the noted Spanish writer.