Answer:
Dante saw Judas Iscariot, Brutus and Cassius during his visit in the Ninth circle of Hell.
They were there because they betrayed their masters or someone close to them.
Explanation:
Dante Alighieri's "Divine Comedy" is a long narrative consisting of three sections that narrate the different phases of the afterlife. The narrative follows Dante in his journey to Paradise, Hell, and Purgatory.
The Ninth Circle of Hell is from the section where he was taken to visit Hell by Virgil. There, he met "Judas, he that hath his head within / And plies the feet without. Of th' other two, / Whose heads are under, from the murky jaw / Who hangs, is Brutus: lo! how he doth writhe / And speaks not! Th' other Cassius, that appears / So large of limb".
Judas Iscariot was there in Hell for betraying Jesus Christ, while Brutus and Cassius betrayed Julius Caesar.
