Born to artisan parents of limited means, he was apprenticed to the sculptor Giuseppe Maria Bonzanigo.

He also studied at the Brera Academy with Giocondo Albertolli and began his career as a set designer in the Teatro Carcano (1804) and La Scala (1805 - 1809), under the direction of Alessandro Sanquirico.

Then, from 1810, he began painting again (mostly miniatures) in watercolours and oils on different media, (canvas, silk, and ivory).

While the Milanese painting scene was dominated by neoclassic painters Andrea Appiani and Luigi Sabatelli, Giovanni Migliara stayed with the historical themes and medieval subtlety of romanticism.

With his improved technique, his choice of subjects, and the quality of his work, he became a favorite of the Milanese aristocracy.