The fortunes of Adelchis' principality are linked to a remarkably turbulent historical period, punctuated by wars in which Emperor Louis II was involved.
By the time Adelchis became prince, no gold coins had been minted in Benevento for about fifteen years, and the only coinage metal remained silver.
With Grimoald IV (806-817) a new type had appeared: on the obverse an ear of corn and on the reverse a cross juxtaposed by four lozenges.
[7] Adelchis' coinage reflects the international political problems experienced by the principality of Benevento during his time as prince.
The first one[10] on the obverse presented in the field, on three lines, the legend + / ADEL' / PRIN and on the reverse a cross set aside by four lozenges, surrounded by the legend - ARHANGEMIHAE ("Archangel Michael"), very similar to the reverse of the deniers of Grimoald IV with the spike, part of the Lombard coinage of Benevento.
The third type[14] had in the field the letters P ADL R (Adelchi Princeps) arranged in three lines to form a cross, surrounded by the legend + SANCTA MARIA.
In his fourth coinage, dated 812-814, Charles had introduced the type of deniers with an imperial, Roman-style portrait used for the obverse.
[21] The temple motif was also used in the coinage of Louis the Pious,[22] with differences in the legend, which became XPISTIANA RELIGIO with the letter "S" instead of Charles' lunate sigma.
[15][19] The seventh type[25] presented on the obverse a monogram of the name Adelchis[26] surmounted by a "∇" and flanked on the right by a cross and on the left by a monstrance.
On the reverse the coin featured the legend - BENE - - - BENTV around a cross on three steps flanked by the letters "M" and "H" (for Michael Angelus).
This situation is evidenced by the issues of this period, those of the years 867-871, which saw deniers coined with the joint names of Adelchis and Louis II.
[28][29] In this case the types used were mostly taken from earlier imperial coinage: the Carolingian temple, the cross with the legend + XPSTIANARELIGI (christiana religio) and others.
In other coins the name of Louis' wife appeared in the form of ANGILBERGA, accompanied by titles such as DMA (domina), IMP (imperatrix) or AGVSTA (augusta), with various spellings.