[1] Vigilant carries the Trident ballistic missile, the United Kingdom's nuclear deterrent.

[2] Vigilant was built at Barrow-in-Furness by Vickers Shipbuilding and Engineering Ltd (now BAE Systems Submarine Solutions), was launched in October 1995, and commissioned in November 1996.

Two protestors managed to spray paint Vigilant with the CND symbol and the word "Vile".

[7] In October 2017, it was revealed that the vessel's captain had been relieved of his command following allegations of an "inappropriate relationship" with a female crew member.

[8] Along with the captain, his executive officer was also removed from his post amid allegations of an improper relationship with a different female crew member.