The Cimmerians (also Kimmerians; Greek: Kimmerioi, Kimmerioi) were an ancient people, who appeared about 1000 BC  and are mentioned later in 8th century BC in Assyrian records. Probably originating in the Pontic steppe and invading by means of the Caucasus, they are likely to be those who in c. 714 BC assaulted Urartu, a state in north eastern Anatolia subject to the Neo-Assyrian Empire. They were defeated by Assyrian forces under Sargon II in 705 and turned towards Anatolia, conquering Phrygia in 696/5. They reached the height of their power in 652 after taking Sardis, the capital of Lydia; however an invasion of Assyrian controlled Anshan (Persia) was thwarted.

A people named Kimmerioi is described in Homer's Odyssey 11.14 (c. late 8th century BC), as living beyond the Oceanus, in a land of fog and darkness, at the edge of the world and the entrance of Hades.  According to Herodotus (c. 440 BC), the Cimmerians had been expelled from their homeland between the Tyras (Dniester) and Tanais (Don) rivers by the Scythians. Unreconciled to Scythian advances, to ensure burial in their ancestral homeland, the men of the Cimmerian royal family divided into groups and fought each other to the death. The Cimmerian commoners buried the bodies along the river Tyras and fled across the Caucasus and into Anatolia. Herodotus also names a number of Cimmerian kings, including Tugdamme (Lygdamis in Greek; mid-7th century BC), and Sandakhshatra (late-7th century).  In 654 BC or 652 BC - the exact date is unclear - the Cimmerians attacked the kingdom of Lydia, killing the Lydian king Gyges and causing great destruction to the Lydian capital of Sardis. They returned ten years later during the reign of Gyges' son Ardys II; this time they captured the city, with the exception of the citadel. The fall of Sardis was a major shock to the powers of the region; the Greek poets Callinus and Archilochus recorded the fear that it inspired in the Greek colonies of Ionia, some of which were attacked by Cimmerian and Treres raiders.  The Cimmerian occupation of Lydia was brief, however, possibly due to an outbreak of plague. They were beaten back by Alyattes II of Lydia. This defeat marked the effective end of Cimmerian power.  The term Gimirri was used about a century later in the Behistun inscription (c. 515 BC) as an Assyro-Babylonian equivalent of Persian Saka (Scythians). Otherwise, Cimmerians disappeared from the historical record.

Using a quote from the above article, answer the following question: Who were the Cimmerians?
According to Herodotus (c. 440 BC), the Cimmerians had been expelled from their homeland between the Tyras (Dniester) and Tanais (Don) rivers by the Scythians.