The correct answer to this open question is the following.
The hardship that Wilkinson’s expedition faced while traveling through Oklahoma was a harsh winter that froze over the riverbeds.
We are talking about the expedition made by James Wilkinson and his assistant Zebulon Pike through the Southwest of the United States at the beginning of the 1800s. They navigated through the Red River and the Arkansas River, but face harsh weather conditions such as extremely cold winter and frozen rivers.
Wilkinson allegedly became involved in Aaron Burr's attempt to create a separate and independent territory in the Mississippi Valley. Court-martialed in 1811 for his suspected collusion with the Spanish, Wilkinson, holding the rank of general, was acquitted. He so ineptly commanded American forces in the War of 1812 that another court-martial ended his military career.
