Jesus/Joshua was not a unique name at the time of his birth in Bethlehem. The KJV uses Greek versions of Hebrew names in the NT. The Greek name for Joshua is Iesus or Jesus in English. Joshua is also called Jeshua (from Yeshua) in the OT, and he is called Jeshua son of Nun in at least one passage, which makes it clear that it is the same name. The Septuagint uses Iesus in all cases. I'm about halfway done with an article on the topic in which I will discuss the significance of translating it as Jesus. I'll post it soon.

John Hinton
Bible Restoration Ministry