Engelia experienced its golden age, and although the empire allowed most of it's citizens some degree of freedom, three things were demanded from them: To pay taxes, to abide the law and to demonstrate utter patriotism to their own heritage.
However, there were those who did not feel as part of the empire, those that were shunned and cast away. Skinnier, with lighter hair, the Susans and Urans were persecuted for their differences, not only in their appearance, but due to their very way of being. Eventually, it became too much, and they fled, thousands fled, migrating south, to the very edge of the continent, where later on they would found the Twin Cities.