Just like Jesus, there is much controversy about the actual existence of a historical David. But, very different from the life of Jesus, the Bible has a lot to say about the life of King David. The story is covered in most of the second part of the Old Testament, from 1 Samuel to 2 Chronicles, and it is said that if he did not actually author the Psalms, he had a hand in the compilation of them.
Extra-biblical evidence for the existence of David comes from a stele (a basalt inscription) written in Aramaic, discovered by Israeli archaeologist Avraham Biran (1909-2008). A tel is a mound, an artificial mound, covering an ancient settlement.
The stele is damaged and therefore not completely legible but it speaks about victories over local neighbours including “Israel” and the “House of David.”
In The Bible Unearthed, (pages 128/9) Israel Finkelstein and Neil Asher Silberman say:
“biblical descriptions of Solomon clearly suggest that this was a portrayal of an idealized past, a glorious Golden Age...And the archaeological evidence in Jerusalem for the famous building projects of Solomon is nonexistent...Many scholars argue that remains from the Solomonic period in Jerusalem are missing because they were completely eradicated by the massive Herodian constructions on the Temple Mount in the Early Roman period. Moreover, the absence of outside references to David and Solomon in ancient inscriptions is completely understandable, since the era in which they were believed to have ruled (c1009-c930 BCE) was a period in which the great empires of Egypt and Mesopotamia were in decline.
Yet in the summer of 1993, at the biblical site of Tel Dan in northern Israel, a fragmentary artifact was discovered that would change forever the nature of the debate... there is hardly a question that it tells the story of the assault of Hazael, king of Damascus, on the northern kingdom of Israel around 835 BCE. This war took place in the era when Israel and Judah were separate kingdoms, and the outcome was bitter defeat for both.
The most important part of the inscription is Hazael’s boasting description of his enemies:
[I killed Jeho]ram son of [Ahab] king of Israel, and [I] killed [Ahaz]iahu son of [Jehoram kin]g of the House of David. And I set [their towns into ruins and turned] their land into [desolation].
They go on to say: that the ruling house is mentioned, is evidence that David was not a literary invention. They also refer to the Moabite Stone (Mesha Stele), discovered in 1868, which now resides in the Louvre Museum in Paris.
"The skeptics' claim that King David never existed is now hard to defend. Last year the French scholar Andre Lemaire reported a related "House of David" discovery in Biblical Archaeology Review. His subject was the Mesha Stele (also known as the Moabite Stone), the most extensive inscription ever recovered from ancient Palestine. Found in 1868 at the ruins of biblical Dibon and later fractured, the basalt stone wound up in the Louvre, where Lemaire spent seven years studying it. His conclusion: the phrase "House of David" appears there as well. As with the Tel Dan fragment, this inscription comes from an enemy of Israel boasting of a victory--King Mesha of Moab, who figured in the Bible. Lemaire had to reconstruct a missing letter to decode the wording, but if he's right, there are now two 9th century references to David's dynasty."
- TIME Magazine
December 18, 1995 Volume 146, No. 25
December 18, 1995 Volume 146, No. 25
However, what does appear to be a bit of literary exaggeration is the size of David’s Kingdom:
...Middle Bronze age, ...settlement in the highlands..there were very few permanent settlement sites in the south, most of them tiny, and there were a large number of pastoral groups, evidenced by their isolated cemeteries, not related to sedentary sites. The north was much more densely inhabited with settled farmers in much greater proportion than pastoralists. The major urban site in the south was...Jerusalem, which was heavily fortified..., joined by a secondary center, Hebron, which was also fortified....The fourteenth century BCE Tell-el-Amarna letters confirm the partition of the central hill country between two city-states, or actually early territorial states, Shechem and Jerusalem. A number of the letters refer by name to the rulers of these two city states --a king named Abdi-Heba who reigned in Jerusalem and a king named Labaya who reigned in Shechem--each of whom controlled territories of about a thousand square miles. Shechem and Jerusalem, Israel and Judah, were always distinct and competing territories. (The Bible Unearthed p155)
Thus it seems in the 14th century BCE, Jerusalem was not yet settled by the “Children of Israel” which fits in with the biblical story:
Despite Judah’s prominence in the Bible, however, there is o archaeological indication until the eighth century BCE that this small and rather isolated are, surrounded by arid steppe land on both east and south, possessed any particular importance..its population was meager; its towns--even Jerusalem--were small and few. It was Israel, not Judah, that initiated wars in the region. It was Israel, not Judah, that conducted wide-ranging diplomacy and trade. When the two kingdoms came into conflict, Judah was usually on the defensive, forced to call in neighboring powers to come to its aid. Until the late eighth century, there is no indication that Judah was anything more than a marginal factor in regional affairs...Judah seems to have been jut a rather small and isolated kingdom that, as the great conquering Assyrian king Sargon II derisively put it “lies far away.”(The Bible Unearthed p230)
It seems from the archaeology that it possibly existed, but that he was merely a minor king in a very small settlement and not the hero of these verses:
1 Chronicles 18:1 Now after this it came to pass, that David smote the Philistines, and subdued them, and took Gath and her towns out of the hand of the Philistines. And he smote Moab; and the Moabites became David's servants, [and] brought gifts. And David smote Hadarezer king of Zobah unto Hamath, as he went to stablish his dominion by the river Euphrates. And David took from him a thousand chariots, and seven thousand horsemen, and twenty thousand footmen David also houghed all the chariot [horses], but reserved of them an hundred chariots. And when the Syrians of Damascus came to help Hadarezer king of Zobah, David slew of the Syrians two and twenty thousand men. Then David put [garrisons] in Syriadamascus; and the Syrians became David's servants, [and] brought gifts. Thus the LORD preserved David whithersoever he went.
1 Chronicles 20:3 And he brought out the people that [were] in it, and cut [them] with saws, and with harrows of iron, and with axes. Even so dealt David with all the cities of the children of Ammon. And David and all the people returned to Jerusalem.
Thus, it seems that everything written in the Old Testament about the people of the Bible is nothing more than mere exaggeration up to the actual existence of Jerusalem, before it became the capital of Judah. There was a group of people who had some sort of relationship with the herders who lived in the south, it is not until the emergence of David and Solomon (who were minor kings until Omri, who was a pagan, that the history of Judah really begins, therefore in summary:
Israel and Judah emerged from the indigenous Canaanite culture of the Late Bronze Age, and were based on villages that formed and grew in the southern Levant highlands (i.e., the region between the coastal plain and the Jordan Valley) between 1200 and 1000. Israel became an important local power in the 9th and 8th centuries before falling to the Assyrians in 722; the southern kingdom, Judah, enjoyed a period of prosperity as a client-state of the greater empires of the region before a revolt against Babylon led to its destruction in 586. Judean exiles returned from Babylon early in the following Persian period, inaugurating the formative period in the development of a distinctive Judahite identity in the province of Yehud, as Judah was now called. Yehud was absorbed into the subsequent Greek-ruled kingdoms which followed the conquests of Alexander the Great. In the 2nd century BCE, the Judaeans revolted against Greek rule and created the Hasmonean kingdom, which became first a Roman client state and eventually passed under direct Roman rule. Source