In 1540, Spanish explorer Hernando de Soto embarked on an expedition across what is now the Southeastern United States, then called "La Florida," in hopes of finding a route to Mexico.
 Marching north from Florida, De Soto passed through modern South Carolina and North Carolina before turning west and crossing the Blue Ridge Mountains via the Nolichucky Valley into East Tennessee.
 After resting for several weeks at the prominent village of Chiaha (near modern Douglas Dam), De Soto continued down the French Broad River and Tennessee River to the village of Coste, centered around Bussell Island, arriving at its outskirts on July 1, 1540.

De Soto held a friendly meeting with the chief of Coste on July 2, but relations quickly soured after the Spaniards pillaged some of the Costeans' storehouses, and several Costeans attacked the Spaniards with clubs.
 De Soto then devised a ruse in which he kidnapped the chief and held him hostage for several days.
 After the chief promised to assign guides and porters to the expedition, De Soto departed on July 9.
 The expedition continued up the Little Tennessee to the village of Tali (near modern Vonore), and eventually found its way south to Coosa, in northern Georgia.

The inhabitants of Coste, like the inhabitants of Chiaha, spoke a Muskogean language similar to that used by the later Creek and Koasati tribes (linguist Charles Hudson suggests that the term "Koasati" may have been derived from "Coste").
 Coste was probably part of the Coosa chiefdom's sphere of influence, which stretched from the upper Tennessee valley south into central Alabama.
 In 1567, another Spanish explorer, Juan Pardo, visited the villages of Chalahume and Satapo further up the Little Tennessee Valley, but turned back before reaching Coste.
In 1540, Spanish explorer Hernando de Soto embarked on an expedition across what is now the Southeastern United States, then called "La Florida," in hopes of finding a route to Mexico.  Marching north from Florida, De Soto passed through modern South Carolina and North Carolina before turning west and crossing the Blue Ridge Mountains via the Nolichucky Valley into East Tennessee.  After resting for several weeks at the prominent village of Chiaha (near modern Douglas Dam), De Soto continued down the French Broad River and Tennessee River to the village of Coste, centered around Bussell Island, arriving at its outskirts on July 1, 1540.
De Soto held a friendly meeting with the chief of Coste on July 2, but relations quickly soured after the Spaniards pillaged some of the Costeans' storehouses, and several Costeans attacked the Spaniards with clubs.  De Soto then devised a ruse in which he kidnapped the chief and held him hostage for several days.  After the chief promised to assign guides and porters to the expedition, De Soto departed on July 9.  The expedition continued up the Little Tennessee to the village of Tali (near modern Vonore), and eventually found its way south to Coosa, in northern Georgia.
The inhabitants of Coste, like the inhabitants of Chiaha, spoke a Muskogean language similar to that used by the later Creek and Koasati tribes (linguist Charles Hudson suggests that the term "Koasati" may have been derived from "Coste").  Coste was probably part of the Coosa chiefdom's sphere of influence, which stretched from the upper Tennessee valley south into central Alabama.  In 1567, another Spanish explorer, Juan Pardo, visited the villages of Chalahume and Satapo further up the Little Tennessee Valley, but turned back before reaching Coste.
Bussell Island