 Complete the following phrase:  He was commissioned as an officer in 1903 and was promoted to lieutet in the Life Regiment Dragoons K 2 in 1906. Douglas was lieutet in the General Staff in 1913 and served as general staff officer in the staff of the 1st Army Division I. arméfördelningen from 1914 to 1917. He was promoted to captain in 1916 and did the same year a study trip to Galicia region in Central-Eastern Europe. Back in Sweden, Douglas served as a military history teacher at the Royal Swedish Army Staff College in Stockholm from 1917 to 1918 and as general staff officer at the Finnish headquarters during the Finnish Civil War in 1918. During his time in Finland in 1918, he became captain and lieutet colonel in the Finnish Army and took part in the Battle of Länkipohja and 