Because
Jim Thorpe
Persia had no former name, it was always known as Persia.
Thorpe Bates's birth name is Thomas Thorpe Bates.
Alexis Thorpe's birth name is Thorpe, Alexis Ann.
Dee Thorpe's birth name is Duane C. Thorpe.
Graham Thorpe's birth name is Graham Paul Thorpe.
Harriet Thorpe's birth name is Harriet Amelia Thorpe.
Jerry Thorpe's birth name is Richard Jerome Thorpe.
Marilyn Thorpe's birth name is Marylyn Hauoli Thorpe.
Mathilda Thorpe's birth name is Matilda Helen Rachel Thorpe.
There is no former name for it. It has always been known as Lake Tanganyika
The Dardanelles were known as the Hellespont.