The beginning of the last Ice Age is conventionally dated at about 120,000 BCE.

The Eemian, an interglacial period which begins about one hundred and thirty thousand years ago and ends about one hundred and fourteen thousand years ago, is the second-to-latest interglacial period of the current Ice Age, the most recent being the Holocene which extends to the present day.

The prevailing Eemian climate is believed to have been about as stable as that of the Holocene.

Changes in the earth's orbital parameters from today (greater obliquity and eccentricity, and perihelion), known as the Milankovitch cycle, probably lead to greater seasonal temperature variations in the Northern Hemisphere, although global annual mean temperatures are probably similar to those of the Holocene.

The warmest peak of the Eemian is around one hundred and twenty-five thousand years ago, when forests reach as far north as North Cape (which is now tundra) in northern Norway well above the Arctic Circle.

Hardwood trees like hazel and oak grow as far north as Oulu, Finland.

At the peak of the Eemian, the northern hemisphere winters are generally warmer and wetter than now, though some areas are actually slightly cooler than today.

The hippopotamus is distributed as far north as the rivers Rhine and Thames.

Trees grow as far north as southern Baffin Island in the Canadian Arctic Archipelago instead of only as far north as Kuujjuaq in northern Quebec, and the prairie-forest boundary in the Great Plains of the United States lies further west—near Lubbock, Texas, instead of near Dallas, Texas, where the boundary now exists.

Sea level at peak is probably four to six meters (thirteen to twenty feet) higher than today (references in Overpeck et al., 2006), with much of this extra water coming from Greenland but some likely to have come from Antarctica.

Global mean sea surface temperatures are thought to have been higher than in the Holocene, but not by enough to explain the rise in sea level through thermal expansion alone, and so melting of polar ice caps must also have occurred.

Because of the sea level drop since the Eemian, exposed fossil coral reefs are common in the tropics, especially in the Caribbean and along the Red Sea coastlines.

These reefs often contain internal erosion surfaces showing significant sea level instability during the Eemian.

A 2007 study found evidence that the Greenland ice core site Dye 3 was glaciated during the Eemian, which implies that Greenland could have contributed at most two meters (6.6 feet) to sea level rise.

Scandinavia was an island due to the inundation of vast areas of northern Europe and the West Siberian Plain.

Given that the shorelines of the islands of the present are at this time several feet higher, humans of this epoch must have used boats: the large island of Crete in the Aegean basin is settled as early as 128,000 BCE, during the Middle Paleolithic age.

The period closes as temperatures steadily fall to conditions cooler and drier than the present, with four hundred and sixty-eight-year long aridity pulse in central Europe, and by one hundred and fourteen thousand years before the present, a glacial era has returned.