268-270 AD., Claudius II., AE-Antoninianus, Mediolanum mint, RIC157.

Claudius II. (Gothicus), AE-Antoninianus, 3,29 g., Mediolanum mint, issue 2, officina 3, 268-270 AD.
Obv.: [IMP] CLAVDIVS P F AVG , radiate, draped and cuirassed bust right, seen from behind.
Rev.: PA-X - A-VG / T , Pax advancing left, holding (olive?) branch and transverse scepter.
RIC 157 ; C 202 ; Cunetio hoard 2263 ; Normanby h. 1031 ; Chalfont h. 781 .
for the attribution of the mint see Märkl - The Coinage of Claudius II

For the time Gallienus campaigned against the Goths in eastern Europe in 268 AD he had placed Aureolus in command of the legions in northern Italy to protect Rome from invasion by Postumus.
When the emperor was conducting his eastern campaign, Aureolus openly declared for Postumus, and issued a series of coinage in the name of Postumus from Mediolanum. It is uncertain what Postumus's attitude was towards this event, but he obviously was unable to commit any forces (due to Laelianus's uprising) to help Aureolus, who was soon beseiged in Mediolanum by Gallienus.
Nonetheless, during the siege Gallienus was assassinated, and was replaced by Claudius II.
Upon hearing of this event, Aureolus attempted to make peace, but Claudius refused, which forced Aureolus to capitulate, hoping for leniency. In this time of constant upheaval, there could be no room for Claudius to be lenient, and Aureolus was put to death.