PRESENTING THE HIGHEST SCORE IN CIVILIZATION IV HISTORY:
3,381,779 POINTS.
However, this isn't at all the highest score achievable in Civilization 4. As I mentioned, this was limited to CFC HOF rules. You could turn off domination to obviously go much higher, and also it's quite tempting to set Unrestricted Leaders to pick Darius of Holy Roman or Zulu. There's also potential in Deity difficulty, and in using max 17 opponents for even more worker steals, start-normalized capitals to conquer, and tech to trade for. Dammit, now that I wrote this paragraph I kind of want to try that now.
This obviously isn't official for the CFC HOF, since I don't care to use their mod, but you have my word that this game was played honestly. I do reload occasionally for things like misclicks, but never to peek at hidden information or undo combat results or strategic error, and of course nothing here was cheated in Worldbuilder.
Well, there you have it. Thanks to WastinTime for conceiving the original setup, and to my Realms Beyond and Civfanatics audiences for reading along with me. For comments, try the Realms Beyond thread here.