What are some examples of the historical allusions used in Dante's Inferno?

Dante alludes to the feud between the Guelphs and Ghibellines, which dominated the politics of central Italy in Dante's time.

Explanation:

The Guelphs supported the Pope in a power struggle with the Holy Roman Empire. The Ghibellines supported the Holy Roman Empire against the Pope. Guelphs tended to come from the merchant or middle classes, while Ghibellines tended to be land-owning aristocrats.

In the Inferno, Mosca dei Lamberti is being punished in hell for, in Dante's opinion, having started the bitter and bloody feud between the Guelphs and Ghibellines. Mosca is in the ninth circle of hell, the place where the sowers of discord and the creators of papal schism are confined. Mosca must wander around until he encounters the devil, who repeatedly slashes off his arms. Mosca shares this space with another historical figure, Mohammed (or "Mohamet"), who supposedly sowed discord by founding Islam.