Private Walter Fredrick Siewertsen was an English soldier of the British Army who died during the First World War.
He was born in 1894, in West Ham, the son of German-born Hans Christian, a furskin dresser and preparer, and Mary Ann Siewertsen (née Serger), of London. At the time of the 1911 census, Siewertsen had followed into his father's trade and was living with his family at 56 Rosher Road.
He is buried in Zillebeke Churchyard, Belgium.
- Siewertsen, Walter Fredrick, cwgc.org. Retrieved 11 August 2013.