Why is Canon Rebel XSi known as Canon 450D?

Canon has different names around the world for their Rebel (Amateur/Consumer) line of cameras. In the US, the line is known as the Canon Rebel XSi. In Japan, it is alternatively named the Canon Kiss X2 while in Europe and around the world, it is known as the Canon 450D. Canon has done this for at least most of their Rebel cameras. The original Rebel is called the Kiss Digital; the XT is known as the 350D or Kiss Digital N; the XTi is the Kiss Digital X or 450D, the XSi is the 450D or the Kiss X2, and finally, the new XS is the 1000D or the Kiss F. However, the "***D" title (ex. 450D) is often used interchangeably with the "Rebel X**" title (ex. Rebel XSi), even in the US or Japan.