You will need a macro to do this. I think a workable solution would be
along the following lines:

Create a new sheet.
Scan through all other worksheets, recording the name of the sheet and
the region code in the range A1 to B850 of the new sheet.
Sort A1:B850 using region code as the sort key.
Scan through this range in sequence to obtain the worksheet name, and
move the sheet with this name to its appropriate position.

Hope this helps to get you started.

Pete