He Changed the Tang Dynasty

During the Zhenguan era, why was there square dancing to pipa music every night in the neighborhoods of Chang'an, capital of the Great Tang? Why were the heroes of the greenwood in the taverns fighting over a game of Legends of the Three Kingdoms? Why did the princes and princesses of Daxing Palace eagerly await each new issue of Weekly Shonen Jump at the start of every month? Why did carriages speeding across the Great Tang bear the words "Didi Carriage"? I, Li Yi, Ninth Imperial Prince of the Great Tang, just want to invent things, advance technology, draw comics, make money, and, while I'm at it, beat up the Turks, Goguryeo, and Wa... How did I end up being named Crown Prince? Don't panic. Let me recite a poem first.