בְּרֵאשִׁית. Bereshit. Genesis.
The first portion of this book is known to scholars as “primeval history,” and it records the creation of the universe, mankind’s fall into sin, a global Flood, and the dispersion of the nations.
Unfortunately, primeval history is so often overlooked. The most widely accepted positions on this section of Genesis are that it is either poetic or allegorical in nature, partial in truth, or worse, just an ancient myth. Some even go as far as to say that primeval history is not meant to tell us what happened or when it happened, but only to convey theological truths. Sadly, these views are popular even among professing Jews and Christians. Many will argue that the debate over the historicity of Genesis is unimportant and that we should turn our attention to topics they deem more important, like the gospel.
The acceptance of primeval history as true history is not a salvation issue. However, it must be acknowledged as true history if one wants to be biblically consistent.
Why should believers accept Genesis as History?
Simply put, primeval history is recorded as such. Its author used wording that is characteristic of a historical narrative and not other forms of Hebrew literature. The waw consecutive is a grammatical construction used by ancient Hebrew writers. When it appears in writing, it’s purpose is “to present events in a historical sequence. It appears throughout Hebrew narrative, but it is almost non-existent in Hebrew poetry.” 
The historical sequence of events recorded in the early chapters of Genesis is written in the confines of space and time. The author(s) uses straightforward geographic terms when describing the locations where the events it is recording took place, such as Eden in Genesis 2:10-14.
The timeline of the events of primeval history is tied to the rest of Scripture by means of genealogies. These genealogies link historical figures such as Jesus and King David to Abraham and even more ancient individuals like Noah and Adam (Luke 23:23-38). At what point does one draw a line between what parts of the genealogy are historical and which parts are not.
Additionally, the apostles, and even the Messiah Himself, based their teachings on the historicity of the early chapters of Genesis. Paul wrote that it was because of Adam (that is, the first Adam) sin and death entered the world, and it was because of the last Adam (Jesus) that this curse could be reversed (1 Corinthians 15:21-22, 45). The apostle Peter draws parallels to the worldwide judgment brought on by the return of our Messiah in the future to worldwide judgment brought on the people of the pre-Flood world in the past (2 Peter 3:3-7). Last but not least, the Noachian Flood (Luke 17:26-27) and the first human death (Matthew 23:23-35) were considered foundational to Jesus’s own teachings.
For these reasons, it is clear that Genesis is to be interpreted as a historical narrative.
 Currid, J.D., A Study Commentary on Genesis—Volume 1: Genesis 1:1–25:18, Evangelical Press Study Commentary series, Evangelical Press, Webster, NY, p. 38, 2003.