Complex sentence: His assignments included command of Troop B and regimental commissary, and he served at Fort Riley (Kansas), Fort Huachuca (Arizona), the Philippines, Fort Walla Walla (Washington), and Boise Barracks (Idaho).
Split into simpler sentences: His assignments included command of Troop B and regimental commissary. He served at Fort Riley (Kansas), Fort Huachuca (Arizona), the Philippines, Fort Walla Walla (Washington), and Boise Barracks (Idaho).