Hadean
The Hadean () is a geologic eon of the Earth pre-dating the Archean. It began with the formation of the Earth about 4.6 billion years ago and ended, as defined by the ICS, 4 billion years ago. , the ICS describes its status as ""informal"". Geologist Preston Cloud coined the term in 1972, originally to label the period before the earliest-known rocks on Earth. W. Brian Harland later coined an almost synonymous term, the "Priscoan period", from "priscus", the Latin word for "ancient". Other, older texts simply refer to the eon as the Pre-Archean.
Hauran
From the mid-1st century BCE, the region was governed by the Roman Empire's Herodian and Nabatean client kings until it was formally annexed by the empire in the 2nd century CE. The Hauran prospered under Roman rule (106–395 CE) and its villages functioned as largely self-governing units, some of which developed into imperial cities. The region continued to fare well in the Byzantine era (395–634), during which different Arab tribes ruled the Hauran on Byzantium's behalf, including the Salihids (5th century) and Ghassanids (6th century) until the Muslim conquest in the mid-630s. For much of the Islamic era until Ottoman rule (1517–1917), the Hauran was divided into the districts of al-Bathaniyya and Ḥawrān, which corresponded to the Classical Batanea and Auranitis, respectively. Muslim geographers variously described these districts as prosperous, well-watered and well-populated.