Answer:
the influence of the natural world
Step-by-step explanation:
The influence of the natural world inspired American artists in the early nineteenth century, making their work unique. This was evident through the Hudson River Valley School, where great American artists like Thomas Doughty, Asher Durand, and Thomas Cole, worked or painted the eastern part of the natural and open forest and landscape of the Hudson River Valley and near by surroundings such as New England area.
Similarly, the liked of successful Thomas Moran and Albert Bierstadt also worked on the western part of Hudson River Valley, painting the natural world of the area.