Watch List notes:

The Roman Empire

Gaius, 37-41. Sestertius circa 37-38, Æ 27.12 g. C CAESAR AVG GERMANICVS PON M TR POT Laureate bust l. Rev. AGRIPPINA – DRVSILLA – IVLIA The sisters of Gaius standing facing: Agrippina, as Securitas, holds cornucopiae in r. hand resting on column, with l. hand on shoulder of Drusilla, as Concordia, who holds patera and cornucopiae; Julia, as Fortuna, holds rudder and cornucopiae. In exergue, S·C. C 4. BMC 37. RIC 33. CBN 49.
Very rare and in unusually good condition for this difficult and intriguing
issue. A superb portrait and a finely detailed reverse composition,
a lovely brown-green patina and about extremely fine

Ex Gorny & Mosch sale 125, 2003, 394.
Many aspects of Caligula's reign have captured the imagination of historians, but the sexual relationships he is said to have pursued with his sisters is perhaps most shocking of all. It is on par with the exploits of Elagabalus or the alleged seduction of young Nero by his deranged mother Agrippina Jr., who, by no mere coincidence, was one of Caligula's sisters.
Caligula's incestuous relationships with his sisters are alleged by the relatively contemporary historians Suetonius and Josephus. Much later, in the fourth and fifth centuries, these original claims were echoed by various writers, including Eutropius, Aurelius Victor, St. Jerome, Orosius and the anonymous compiler of the Epitome de caesaribus. The truth of the claims, of course, is impossible to confirm, and there is a healthy dose of scepticism among modern scholars.
Whatever personal or sexual affection Caligula may have felt toward his sisters, this coinage is purely political and dynastic in flavour. His sisters are each named and are shown in the guise of personifications: the eldest, Agrippina Junior, as Securitas, the middle-sister, Drusilla, as Concordia, and the youngest, Julia Livilla, as Fortuna.
This remarkable type was produced on two occasions, his initial coinage of 37-38, and again in 39-40. The example offered here belongs to the first coinage, which was issued when all three of the imperial women were alive. Drusilla, Caligula's favourite sister (and the one with whom he is said to have had an enduring incestuous relationship), died tragically on June 10, 38, nearly three months after the last coins of the initial issue were struck.
By the time the last issue was produced (beginning March 18, 39), Drusilla had been accorded the status of a goddess, providing the curious circumstance of a goddess being portrayed in the guise of a personification. Life in the palace worsened after Drusilla's death and Caligula's affection for his remaining two sisters declined.
The circumstances reported by the ancient sources are nothing short of bizarre: Drusilla had been married to Marcus Aemilius Lepidus, who had also been Caligula's lover. After Drusilla died, Lepidus extended his sexual liaisons to include Agrippina and Julia Livilla, his former sisters-in-law. By late in 39 this web of relationships seems to have evolved into a failed plot by Lepidus against Caligula, who executed Lepidus and sent his two sisters into exile out of their suspected complicity.
All of this palace intrigue occurred in the midst of the second issue of 'three sisters' sestertii, the production of which Caligula probably halted immediately since of the three sisters shown, one was dead and two were in exile for having plotted against his life.