He was born in Barlassina on July 9, 1859, fourth of twelve children, from Garibaldi’s volunteer and horseshoer Matteo Longoni and from tailor Luigia Meroni.
In 1876, he joined the regular courses, along with Gaetano Previati and Giovanni Segantini, with whom he shared a studio in 1882.
[1] In 1882 he met Giovanni Segantini, already his classmate in Brera, who introduced him to the brothers Alberto and Vittore Grubicy, owners of an art gallery that was active in promoting young artists.
After the first world war he shut himself up, his age forbade him to go to the high mountains while his painting became more and more immaterial.
Since 2002 the record price for this artist at auction is $335,910 USD for natura morta con frutta candita e caramelle, studio dal vero, sold at Sotheby's Milan in 2007.