Did you know that many Bible archaeologists thought that David never even existed?
The archaeologists also said that Jerusalem wasn't even a city at the time David was supposed to have lived. However, in 1993 archaeologists made a huge contribution to this debate. While cleaning up an excavation at the biblical Dan, someone noticed an inscription on a stone. It turned out to be part of a victory monument erected by an Aramean ruler celebrating a victory over Israel. On that inscription were words translating to "House of David, King of Israel."
Believers don't need such evidence to know that the Bible is trustworthy when it talks about historical events. However, now there can be no question that David was a person just as real as you.