What's the actual evidence?
Two royal public buildings, the likes of which have not previously been found in the Kingdom of Judah of the tenth century BCE, were uncovered this past year by researchers of the Hebrew University and the Israel Antiquities Authority at Khirbet Qeiyafa – a fortified city in Judah dating to the time of King David and identified with the biblical city of Shaarayim.AP adds:
One of the buildings is identified by the researchers, Professor Yossi Garfinkel of the Hebrew University and Saar Ganor of the Israel Antiquities Authority, as David’s palace, and the other structure served as an enormous royal storeroom.
Today (Thursday) the excavation, which was conducted over the past seven years, is drawing to a close. According to Professor Yossi Garfinkel and Sa'ar Ganor, “Khirbet Qeiyafa is the best example exposed to date of a fortified city from the time of King David. The southern part of a large palace that extended across an area of c. 1,000 sq m was revealed at the top of the city. The wall enclosing the palace is c. 30 m long and an impressive entrance is fixed it through which one descended to the southern gate of the city, opposite the Valley of Elah. Around the palace’s perimeter were rooms in which various installations were found – evidence of a metal industry, special pottery vessels and fragments of alabaster vessels that were imported from Egypt. The palace is located in the center of the site and controls all of the houses lower than it in the city. From here one has an excellent vantage looking out into the distance, from as far as the Mediterranean Sea in the west to the Hebron Mountains and Jerusalem in the east. This is an ideal location from which to send messages by means of fire signals. Unfortunately, much of this palace was destroyed c. 1,400 years later when a fortified farmhouse was built there in the Byzantine period”.
A pillared building c. 15 m long by 6 m wide was exposed in the north of the city, which was used as an administrative storeroom. According to the researchers, “It was in this building the kingdom stored taxes it received in the form of agricultural produce collected from the residents of the different villages in the Judean Shephelah. Hundreds of large store jars were found at the site whose handles were stamped with an official seal as was customary in the Kingdom of Judah for centuries”.
The palace and storerooms are evidence of state sponsored construction and an administrative organization during King David’s reign. “This is unequivocal evidence of a kingdom’s existence, which knew to establish administrative centers at strategic points”, the archaeologists say. “To date no palaces have been found that can clearly be ascribed to the early tenth century BCE as we can do now. Khirbet Qeiyafa was probably destroyed in one of the battles that were fought against the Philistines circa 980 BCE. The palace that is now being revealed and the fortified city that was uncovered in recent years are another tier in understanding the beginning of the Kingdom of Judah”.
Garfinkel said his team found cultic objects typically used by Judeans, the subjects of King David, and saw no trace of pig remains. Pork is forbidden under Jewish dietary laws. Clues like these, he said, were "unequivocal evidence" that David and his descendants had ruled at the site.The archaeologists seem to have dated the structure quite precisely to the time of David's reign, which was from 1002–970 BCE, or shortly thereafter. They identified the seals in the storerooms as being from Judah. There is no evidence of non-kosher animal bones. (We know the Philistines raised and ate pig meat; there is disagreement among scholars whether Canaanites ate pork as well. They apparently ate donkey at times.) Also, there is evidence of some Hebrew writings at the site.
Critics said the site could have belonged to other kingdoms of the area. The consensus among most scholars is that no definitive physical proof of the existence of King David has been found.
Garfinkel believes King David lived permanently in Jerusalem in a yet-undiscovered site, only visiting Khirbet Qeiyafa or other palaces for short periods. He said the site's placement on a hill indicates that the ruler sought a secure site on high ground during a violent era of frequent conflicts between city-states.
"The time of David was the first time that a large portion of this area was united by one monarch," Garfinkel said. "It was not a peaceful era."
Definitively calling this "David's palace" seems a little premature to me, but Khirbet Qeiyafa seems to be very good proof of the early Judean kingdom.