History of the Jewish kings is irrelevant to my daily life; what is relevant is what they say in the Bible and what they do; the combined message. They might as well be fictitious for all I know, but it's the message behind the story that counts.
You say they all believed in the Prophets. So the Bible says. And for all practical purposes we believe it too, but it's not their historical reality or fiction that matters but the message they project.
As for historical veracity of the Bible, that is a matter of debate as you know. Very few things mentioned in it are readily verifiable, including any reference by anyone (save for Josephus, in pasisng, and some 30 years later, and based on what he has been told by Christians!) who make reference to Christ. If His presence was such a threat to the Jews and to Rome, something other than the Bible would surely be recorded. Yet, mysteriously, nothing of God's presence, no relics of His have been preseved, although they are the holiest of holies -- the ark, the tablets, the grail, the cross, etc.
We make sure our family hairlooms are passed on from generation to generation, yet we lose things God touched, save for a written account we call the Bible. Why? Because nothing else matters except His message, A. Things of this world that were His would become the subject of worship, people would fight over them, so God made sure nothing of His that is material is preserved. Only His Spirit.
The work of Rohault de Fleury, "Mémoire sur les instruments de la Passion" (Paris, 1870), deserves more prolonged attention; its author has sought out with great care and learning all the relics of the True Cross, drawn up a catalogue of them, and, thanks to this labour, he has succeeded in showing that, in spite of what various Protestant or Rationalistic authors have pretended, the fragments of the Cross brought together again would not only not "be comparable in bulk to a battleship", but would not reach one-third that of a cross ...
Other scientific study of the extant relics has been conducted which confirms that they are from a single species of tree. Four cross particles from European churches, i.e. S.Croce in Rome, Notre Dame, the cathedral of Pisa and the cathedral to Florenz, were microscopically examined. "The pieces came all together from olive." (Ziehr, William, Das Kreuz, Stuttgart 1997, Seite 63)