Lucus

Lucus is Lucalis's alternate timeline where


 * the Arabs never conquered Persia but discovered the Americas instead


 * Islamic culture was consequently never Persianized, but instead heavily influenced by Coptic culture, and later willy-nilly by Mesoamerican culture


 * The Central Asian Turks were converted to Zoroastrianism rather than Islam, and the Hagia Sophia was turned into a fire temple.


 * In 1066 Harold Hardrada of Norway conquered Northumbria and William of Normandy conquered southern England, while an Anglian aristocratic republic arose as a buffer zone in the Midlands.


 * The Hundred Years War was about the Northern English driving out the Normans, and about the king of France trying to gain control over his nominal vassals. He eventually regained Normandy but permanently lost Borgonze.


 * the Norse actually colonized Vinland

The adjective for 'belonging to Lucus' is Lucal.