During WWI the following theatres of war existed:
If a man or woman was posted into any of these regions they were considered to have served in a theatre of war and will be in this index.
It follows that any person serving in a theatre of war would be entitled to one or more campaign medals for the conflict also.
Please be aware that due to the way we collate, and cross reference our databases, some records will contain more information than that listed above.
Original Source: National Archives reference WO372 Medal card indices.