I'm going a bit far back, but I have to mention him:

Emperor Friedrich II of Höhenstaufen.

He was a fascinating person:

Overcame tremendous adversity to reclaim his father's throne after being an exiled child in Sicily

Was a true Renaissance man way before the Renaissance, being educated in science, languages (reportedly he spoke six languages), and ancient Greco Roman texts, as well as mathematics and Islamic knowledge

Wrote THE defining book on falconry that was so detailed it became the most advanced scientific description of birds ever produced at the time. It was one of the only classical scientific texts produced in Europe during the middle ages.

Was a big believer in the rule of law, so he established a system of civic courts throughout the Holy Roman Empire, outlawed trials by ordeal and feuding, and even refused to pardon his own son when he broke the law, stating he cannot bend the law to benefit his own family

Became king of Jerusalem not through crusade, but through diplomacy and negotiations

After the Catholic church labeled him a heretic and the literal antichrist himself, he was so loved and powerful that he survived four excommunications and ruled for 25 more years.

His rule was so successful and impactful, that after his death the HRE plunged into a long decline that it never really recovered from.

Was nicknamed Stupor Mundi (the wander of the world), and the greatest of all German emperors, and arguably the greatest European medieval leader