Establishment and independence
The first Chinese person to sight the Vanaheimian coast was Admiral Zheng He serving the Ming Dynasty on his fifth great voyage in 1417. He sailed down the coast, trading gifts with the various indigenous Skraelings he encountered on the way, eventually reaching as far south as the land of the Mexica. In 1418 he returned to China, carrying with him many valuable gifts and a few Skraeling envoys to pay tribute to the Yongle Emperor.
In 1421 he made a second voyage to Vanaheim, returning the envoys to their own people. He also brought two treasure ship loads of Chinese settlers, who he left to found a colony near modern-day Tianshi. It's unknown what happened to the settlers, but later voyages found no trace of either the settlement or its inhabitants.
After that, there were no more voyages for over a hundred years due to the isolationist policies of later Ming emperors. However, during the reign of the Jiajing Emperor, the voyages were allowed to resume, and by 1550 there were dozens of flourishing Chinese settlements all along the coast, on relatively good terms with most of the natives. However, by 1620 the Tianqi Emperor had forbidden all overseas travel once more, and the colonies were forced to look to their own affairs.
With no support from home, the colonies chose to band together for their own protection, creating the original Fusang - but they still considered themselves citizens of China. In 1644 the Ming Dynasty fell amidst civil war and invasions from the north, and the fighting prompted many thousands of refugees to flee overseas to bolster Fusang's numbers.
By 1680 the new Gong Dynasty had re-established order, and demanded that Fusang return the hundreds of Ming loyalists and political dissidents who had settled in Vanaheim. Fusang refused, prompting the Gong to gather a vast army and fleet to seize the dissidents by force, and the Fusangers in turn prepared to defend them.
The resulting war cost many lives on both sides and nearly bankrupted the Gong. In 1688 the Fusangese and their Skraeling allies, after much debate, decided that they should declare independence from China, and by 1692 they had become close to realising it.
The War of Fusangese Independence finally ended in 1693, with the Gongformally recognising the loss of the Vanaheimrian colonies.
Since 1693, Fusang has thrived. The original Chinese settlers were soon joined by newcomers from Japan, Koryo, and New Aragon, as well as Skraelings who adopted Chinese culture and assimilated into the settled population. The Chinook, Salish and Miwok nations, in particular, were quick to assimilate.
From the original colonies around Tianshi, Zhengzhou and Sudao, settlers quickly spread out both inland and along the coast, taking over vast swaths of land either by treaty or conquest. In the 19th century Fusang fought a brief war with Albic Vinland over the border through the Perioecian Mountains, and it had a long-running dispute with Japan over Alasija and the Xiliu Islands. Both conflicts were, however, ultimately solved peacefully.