Which painting focuses on early exploration around 1840?

The painting that focuses on early exploration around 1840 is "The Discovery of the Mississippi by DeSoto." This artwork, created by the painter William H. Powell, depicts the moment when Hernando de Soto first encounters the Mississippi River in the year 1541. The work emphasizes the themes of exploration and discovery, highlighting the important historical narratives associated with early European expeditions in North America.

In contrast, the other paintings address different historical events: "Landing of Columbus" commemorates Christopher Columbus's arrival in the Americas in 1492, while "Embarkation of the Pilgrims" captures the Pilgrims' departure to America in 1620. Lastly, "Baptism of Pocahontas" illustrates a specific event in 1613 involving Pocahontas and reflects later colonial encounters. Therefore, "The Discovery of the Mississippi by DeSoto" is the appropriate choice as it closely aligns with the timeframe of exploration specifically mentioned in the question.