Born to a wealthyMilanesefamily, Praga destroyed himself largely through alcohol and drugs after his father's death plunged the family into poverty. He had been a painter before turning to poetry with Tavolozza. He became a leading presence in the Milanese Scapigliatura, writing its artistic manifesto with Camillo Boito in 1864. He published stories and libretti, as well as the poems of Penombre and Fiabe e leggende. A novel, Memorie diun presbiterio, was completed after his death by Roberto Sacchetti.