The St. Fagan was a Saint Class Admiralty Tug, one of a fleet especially built for the Royal Navy. Most naval bases were reliant, to a degree, on civilian tugs to operate; in order to supplement them, the Navy ordered their own fleet of tugs. When hostilities broke out in 1914, the Royal Navy owned seven tugs, of which the majority had been purchased from civilian sources. There was an immediate need for additional tugs for use in the bases, along with further vessels for use as minesweepers and host of other purposes. A total of 100 civilian tugs were thus drafted into the Royal Navy. As the scourge of the U-Boat in The Great War began to intensify, it became clear that more tugs were needed, both t aid in the recovery of damaged ships and to take the war to the U-boats in the form of anti-submarine patrols. In order to breach this gap, the Admiralty placed an order for 64 tugs built to their own specifications. Based on the standard civilian tug design of the day, they essentially differed by the inclusion of a radio and armament.
The Saint Class formed the core of this new fleet, although of the 64 ordered, only 46 were actually completed before the end of hostilities. St. Fagan was built by Lytham Shipbuilding & Engineering Co., was launched in September, 1918 and commissioned in March of the following year. She was under the command of Lt.Cdr. George Henry Warren, MBE, RN (whose letter we have quoted from) when she was sunk on June 1st 1940, three miles of the French coast.