who was his predecessor?
Tiberius.
Caligula
Following the death of Tiberius, Caligula succeeded his adoptive grandfather as emperor in 37.
which emperor loved greek culture and adopted the wearing of a beard UNANSWERABLE where did caligula reign/ Rome. during which time? AD 37 to 41.
wiki:1597172
Caligula [SEP] Introduction
When Germanicus died at Antioch in 19, Agrippina returned with her six children to Rome, where she became entangled in a bitter feud with Tiberius. The conflict eventually led to the destruction of her family, with Caligula as the sole male survivor. Untouched by the deadly intrigues, Caligula accepted an invitation in 31 to join the emperor on the island of Capri, where Tiberius had withdrawn five years earlier. Following the death of Tiberius, Caligula succeeded his adoptive grandfather as emperor in 37. There are few surviving sources about the reign of Caligula, though he is described as a noble and moderate emperor during the first six months of his rule.