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Fu Qiong, according to the book, appeared out of nowhere and swiftly defeated the gang leader of a bandit group that was taking residence in the Cardinal Kingdom. 

He then slowly defeated everyone and turned the Cardinal Kingdom into his own land. He then slowly started declaring wars against the rest of the kingdoms and one by one defeated them. 

It took him 8 years to fully destroy all the 18 different kingdoms that were available at the time and took them all under his own rule. 

Once the land was too large to keep calling it a kingdom, he took the chance to call his land an empire and named it the Crimson Empire. Then he named himself an Emperor as well. 

Fu Qiong ruled as the first Emperor of the Crimson empire for nearly 6 decades before he retired and passed along his throne to his first son.