Building a King - D&D known Heroes
I will maintain the 2E King Arthur stats, but he will be a simple fighter for all the class mechanics.
Strength: 19 (modifier: 4); Dexterity: 15 (modifier: 2); Constitution: 18 (modifier: 4);
Intelligence; 17 (modifier: 3); Wisdom: 18 (modifier: 4); Charisma: 18 (modifier: 4).
Arthur's level as determined via the 3RD Edition Conversion Manual, is Level 17.
Hit Points - The fighter's hit die is a d10, and his constitution bonus is 4. If at each level he were granted (or rolled) maximum hit points (a favorite house rule of mine!) by level 17 he'd have 238 HP.
Armor class: 21
Base Attack Bonus: Arthur would get 4 attacks at level 17 at the following bonuses: 17/12/7/2
Saving throws: Fortitude: 10, Reflex: 5, Will: 5.
Skill Points: The fighter gets 2 + Intelligence modifier (3) multiplied by 4 for first level. This is 20. However, because he's a Human, he gains an extra 4 at first level, bringing the total to 24. Every level after, he gets 5 (2 + int), with a bonus of 1 for being human. By level 17, King Arthur would have a total of 120 skill points to allocate. Remember, the max for Class Skill is character level +3. (It's half that, rounded down for cross class!) The most you can spend on any given skill for King Arthur is 20 for class, and 10 for cross class.
Feats: One of the biggest benefits to being a Human fighter is the feats. Normal characters get one feat at first level, and then one every third, starting at 3rd level. So, one at 1st, one at 3rd, one at 6th, one at 9th, etc.
Humans gets an extra at level 1. Fighters also get an extra at level 1, and then one every second level, so another at 2nd, another at 4th, etc. By level 17, King Arthur has 16th slots for feat allocation.
Remember when allocating skills and feats, King Arthur was a highly influential and inspirational leader. I'd recommend maxing out diplomacy. You may need to scour some of the supplemental books to find the right skills and feats to account for his leadership skills.
Given his fighting prowess, he'd almost certainly have to have at least great cleave and weapon focus for his sword.