Reborn as a Useless Emperor

Tang Emperor Li Shimin's soul enters Ming Emperor Kieran Sterling. He reverses Ming's fate, creating a golden age. He crushes Oirats, subduing Jurchens. He develops firearms, rebuilds Zheng He's Treasure Ships, lifts sea ban, reopens Maritime Silk Road. He reclaims Annam, conquers Chagatai, establishing its Protectorate. He forces Timurid Empire into vassalage, opening overland Silk Road. Domestically, he promotes potato, tames Yellow River, taxes gentry.