Possibly Jemorah or his son Ahaziah of the house of David, or Ahab of the house of Omri, all corroborated by 9th century BCE monuments; the Tel Dan stele and the Kurkh monoliths respectively. Both are royal inscriptions from neighboring polities describing conflicts with those kings of Israel.

There was a bit of controversy over the authenticity of the Tel Dan stele but it doesn’t seem like there was anything substantial behind it, except for the fact that David is still a politically charged figure. Especially seems that way when you consider how little scrutiny has been given to the inscriptions mentioning the less charismatic, more obscure king Ahab.

People have made claims about the historicity of older figures such as Abraham, but I don’t think they’re credible. If any are, I haven’t seen the evidence.