When the First World War broke out he took part in the operations that resulted in the destruction of the in German East Africa, and was Mentioned in Despatches in 1915. For his actions leading to the capture of Dar es Salaam he was appointed a Commander of the Order of St Michael and St George on 1 January 1918. He was also invested by the Sultan of Zanzibar with the Order of the Brilliant Star of Zanzibar, Second Class. From 1918 to 1919 Anderson was posted to command the battleship in the Grand Fleet. In May 1921 he was appointed as an aide-de-camp (ADC) to King George V, which he held until April 1922. After a posting in England, he was promoted to rear admiral in 1922. On 2 June 1923 he was invested as a Companion of the Order of the Bath. He was later posted from August 1923 to October 1925 as the Senior Naval Officer, Yangtze and briefly served as temporary Commander-in-Chief China Station in 1925. While in China, he was called upon on three separate occasions to command a multi-national force of Japanese, British, American, Portuguese and Italian sailors to help protect the Shanghai International Settlement. For his efforts in China, he was awarded the Order of the Rising Sun, Third Class, by the Emperor Hirohito of Japan.