Ducitora

Ducitora is a location in The Crown & The Flame series. It is popularly known among the Five Kingdoms as the Iron Empire, is a massive empire across the Ocean from the continent where the Five Kingdoms are located. It was once ruled by Empress Azura for over a thousand years until her death in Book 3, Chapter 16. She oversaw the transformation and technological advancement of the realm.

Due to its technological edge over the Five Kingdoms, it also has a superior military. The military edge possessed by the Iron Empire allowed them to threaten the very existence of the Five Kingdoms before the events of Book 1.

History
Over a thousand years ago, the lands that made up the Iron Empire were originally various kingdoms. This changed when Azura, a member of a dying tribe from the Stormlands, challenged the King of Marossi into a riddle contest. If she won, she would succeed him as ruler. If she lost, he would marry her. She won and became the new Queen of Marossi, starting a campaign of conquest against other kingdoms through similar tactics. With each conquest, Marossi expanded until it covered the entire western continent of Ducitora. By then, she renamed it the Iron Empire, with Marossi as its capital.

According to Azura's daughter Lia, however, it was implied that Azura killed the King of Marossi after seizing power from him through dishonest means.

After officially declaring her kingdom an empire, Azura reached the Five Kingdoms and gave them an offer to join her empire in exchange for improvements in living standards and the local rulers retaining their titles. The inhabitants refused, starting a centuries-long war between the Iron Empire and the Five Kingdoms that ended with Azura's defeat and death at the hands of Queen Kenna Rys of Stormholt.

Trivia

 * While the Five Kingdoms seem to resemble Medieval Europe, Ducitora, particularly Marossi, the capital city, seems to resemble typical advanced Western City.
 * T he map of the Five Kingdoms resembles a map of Western Europe while the map of Ducitora resembles North America, specifically Canada and the United States.
 * Ducitora's status as an Empire (compared with Stormholt, Bellmere, Abanthus, Fydoria, and Ebrimel which are "Kingdoms") and its massive size suggest it might have been divided into several smaller kingdoms in the past.

Reference

 * 1) Image source: pixelbatsy ; https://pixelbatsy.tumblr.com