Frederick Barbarossa was succeeded by his sons, Henry and Philip. Both were capable rulers who looked to follow in their father’s footsteps and expand imperial power. Henry had significant successes, but neither lived long enough to truly become remarkable emperors. And they were succeeded by the rival Welf clan, although that King, Otto, didn’t last too long on the throne, either.

Frederick Barbarossa was Holy Roman Emperor in the 12th century. He forced his way into the imperial office, and then forced the office back into relevance after a century or so of decline. He was an incredibly energetic leader, a strong general and politician. He expanded the power of his empire, and is considered one of the greatest of the Holy Roman Emperors.

Yuknoom led the powerful Maya kingdom ruled by Snake Dynasty. He installed vassal kings in neighboring cities and succeeded in dividing the royal line of his main rival, the city of Tikal. He eventually sacked Tikal itself, and continued to grow the power and influence of his city, in what many historians consider the golden age for the Snake Kingdom.

Harsha took over a growing kingdom in eastern Punjab, during a time of divided polities after the collapse of the huge Gupta Empire. He expanded his lands east along the Ganges river, absorbing kingdoms along the way, before uniting lands to the west and further south, eventually creating an empire that ruled almost all of Northern India.

Kanishka led the Kushan Empire at its height, connecting China and India to lands west in the early era of the Silk Road. Kanishka was a strong leader who expanded the empire, stabilized it, and help connect cultures and cultural ideas across Asia.

Mithridates took charge of a relatively small kingdom that nominally held lands south and east of the Caspian sea. By the end of his reign, he had turned it into a powerful empire that ruled from Syria to India, and had grown to be the major rival to the power to their west, the Roman Empire.

Bardylis united the tribes of Illyria in the late 5th and early 4th century BC, created a powerful kingdom that held sway over Macedon and threatened the Peloponnese, and may have helped drive the development of the combined warfare that would allow Alexander to conquer the Persian Empire.

Argishti ruled the ancient kingdom of Urartu, located in today's Armenia and Eastern Turkey. During Argishti's reign in the 8th century BC, Urartu held sway over its powerful neighbor, the Neo-Assyrian Empire

Gaspar Yanga was possibly born as royalty, although no one is sure, but when he died he was certainly considered by many to be a king. Captured in Africa, brought to the Americas, he soon escaped enslavement near Veracruz in today’s Mexico. He soon became the leader of a community of others who escaped, but they were hunted by the Spanish authorities. Yanga led the resistance, and won, not only the freedom of him and his people, but also official recognition by the crown.

Abbas the Great, the shah of the Safavid empire, was great military leader, reformer, and diplomat. He took a shrinking, disintegrating Persian empire and enabled it to grow its greatest extent, in no small part because of his own personal military campaigns