In ancient times, the rione was densely populated; Monti was home to the Forum Romanum and the so-called Suburra, where poor people lived, full of disreputable locals and brothels.

In the Middle Ages the situation was completely different: the Roman aqueducts were damaged, and it was very difficult to bring water to Monti since it was on the hills.

Hence many inhabitants moved to Campus Martius, a lower level part, where they could drink the water from the river Tiber.

Still in the Middle Ages the inhabitants of Monti, called monticiani, developed a strong identity: their Roman dialect was different from that spoken in the other rioni.

Thanks to its position, Monti is full of archaeological sites such as: To the north, the rione borders with Trevi (R. II), from which it is separated by the Foro Traiano, Via IV Novembre, Largo Magnanapoli, Via XXIV Maggio and Via del Quirinale; and with Castro Pretorio (R. XVIII), the boundary being defined by Via delle Quattro Fontane, Via Agostino Depretis, Piazza dell'Esquilino and Via dell'Esquilino.