Thomas et al. (2007) identified earthquake destruction (Earthquake V) within a collapse layer that they associated with the 363 CE southern Cyril Quake. A terminus post quem of 360 CE was established through coins and pottery. They reported that “thin wall construction and surface layers produced pottery from the mid to late fourth century A.D. (similar types to Phase 2 described earlier).” They further noted that “the latest pottery dates from about A.D. 360 onward (based on several examples of African Red Slip form 67, introduced ca. A.D. 360; Hayes 1972).” In addition, “over 100 coins were found on the final floor of this phase. The majority of these coins were found associated with the remains of a broken box in Room 2. The latest coins date to the reign of Constantius II, who reigned from A.D. 337 to 361 (Parker 1999a), and provide a terminus post quem for this building phase.”

They concluded that “the very refined pottery and coin dates give a secure post A.D. 360 date for the Earthquake V event.” Moreover, “the scarcity of post A.D. 360 pottery and the location of the coin hoard at the interface between occupation surface and collapse horizon indicate that this event cannot have occurred long after A.D. 360.” On this basis they interpreted the destruction as “the historically attested earthquake of May 19, A.D. 363 (Russell 1980; Guidoboni 1994: 264–67).”

Powers (2010) provides additional context, observing that “at the end of the troubled third century, the Legio X Fretensis was transferred from Jerusalem to bolster the Limes Arabicus, with the effect that the population increased substantially and the city emerged as a regional centre.” He adds: “A church was built in c. 300 – one of the oldest in the world – testifying to the early progress of Christianity in Palestine; it was apparently destroyed by the earthquake of 363 and subsequently covered by the new city wall.” That wall, “of stone and mud-brick, was complete by the late fourth or early fifth century, suggesting something of the seriousness with which the continued threat of Saracen raiding was taken.”

These developments occurred within the broader imperial framework created by the reforms of Diocletian, under which Aila’s military and urban growth took shape.