The Fracture caused massive earthquakes and hurricanes which tore the world apart. Part of the city was swept up by the storm before being thrown into the middle of the ocean.

Search and Rescue Expeditions were quickly formed in order to bring back survivors left in Old Lumiere but none returned besides the Painted family.

Sophie and Gustave were engaged before they broke up because of their differing views on raising children in Lumière.

Lune is sometimes plagued with imposter syndrome which makes her seem cold and distant despite the depth of her passions.

Gustave is explicitly stated to suffer from PTSD after the ambush.

The Ancient Sanctuary is a cemetery where Gestrals are placed to rest while they wait to be reborn in the Sacred River.

Verso painted the Sacred River because he felt that Immortality was too boring and death was too permanent, and so the reincarnation process of Gestrals leaves only most of their memories intact so that they may still feel excited for new beginnings.

The Painting Workshops (Clea's Atelier as it's known in the game files) were created after the fracture by Clea when she came back to create the nevrons.

The Stone Faced Cliffs was originally populated before the Fracture. The Paintress cult plotline we see is because a few survivors saw her as a deity and worshipped her with carved alters. "Their molten wax bodies now mingle with the candles lit in her name."

The battles of Forgotten Battlefield were fought between humans and nevrons. The marble fortresses, trenches, catapults, and cannons we see were made by the scholars, engineer, and defense forces of the large expeditions participating in the battle. The Nevrons ultimately overcame the courage of the Expeditioners and lead to colossal losses.