Early history of the Isbell family in England, where the name is spelled Isbell since the 1300s, is that the family was from Normandy, came to England in or soon after 1066, and originally spelled the name Isabelle. Isbell appears to be a Spanish spelling of the name, however, doesn't it? Do you have any interesting information on your ancestors while they still lived in Normandy?
There is another version of the Isbell history that states Isbell was a Scottish name and would appear to be unconnected to the Norman-French Isabelles, if true. There was an Ysabel family in an old book on coats of arms of families from the Continent.