Complex sentence: During the course of the war the regiment raised an additional 18 battalions, and in total 16 battalions of the Gloucestershire Regiment saw active service during the war; in France and Flanders, Italy, Gallipoli, Egypt, Mesopotamia, Persia, and Salonika.
Split into simpler sentences: During the course of the war the regiment raised an additional 18 battalions. In total, 16 battalions of the Gloucestershire Regiment saw active service during the war; in France and Flanders, Italy, Gallipoli, Egypt, Mesopotamia, Persia, and Salonika.