It is a Roman marble group depicting a man in the act of plunging a sword into his breast, looking backwards defiantly while he supports the dying figure of a woman with his left arm.

The sculpture group made its first appearance in a Ludovisi inventory taken 2 February 1623, and was possibly found in the grounds of the Villa Ludovisi, Rome, shortly before that. The area had been part of the Gardens of Sallust in Classical times, and proved a rich source of Roman (and some Greek) sculpture through the 19th century (Haskell and Penny, 282). Among the last of the finds at Villa Ludovisi, before the area was built over, was the Ludovisi Throne.

The sculpture, now in the Museo Nazionale di Roma, Palazzo Altemps, Rome, was greatly admired from the 17th century. It appeared in engravings in the repertory of sculpture in Rome by Perrier and was codified by Audran as one of the sculptures of Antiquity that defined the canon of fine proportions of the human body. Nicolas Poussin adapted the figure for the group in the right foreground of his Rape of the Sabine Women, now at the Metropolitan Museum of Art (Friedlaender 19 and fig. 108). Visitors and writers of guidebooks found many subjects drawn from Roman history to account for the action: the 1633 Ludovisi inventory lists it as "a certain Marius who kills his daughter and himself", drawing upon the story of a certain patrician Sextus Marius, who in seeking to protect his daughter from the lust of Tiberius, was accused of incest with her.

According to wikipedia