Vortigern was ordered from J. Samuel White, of Cowes, Isle of Wight during the First World War under the 1916–17 Programme Build (9th Order), and was laid down on 17 January 1917. She was launched on 5 October 1917 and commissioned on 21 January 1918. She has been the only ship of the Royal Navy so far to be named HMS Vortigern, after Vortigern, an early British ruler.
