Three works sum up the entire artistic development of Pietro Aldi. Iphigenia Condemned to Sacrifice by Agamemnon is an early work, made when he was still a student in Siena, while the preparatory study for The Triumph of Judith, a canvas presented at the Vatican Exposition in 1888, and the bozzetto for Nero Watching Rome Burn, intended for the Universal Exposition in Paris in 1889, represent the last works made by the artist before his untimely death on 18 May 1888.

The comparison between his early works and those made as a mature artist reveals the rapid evolution in style and culture which took place in a few short years: from the Purist drawing style of his beginnings, dependent on the study of the Renaissance masters, to the broken, luminous brushwork of his late period, evoking the decadent, sinful environments dear to the burgeoning Symbolist movement.