HMS Bulwark was one of five London-class pre-dreadnought battleships built for the Royal Navy at the end of the 19th century. The Londons were a sub-class of the Formidable-class pre-dreadnoughts. Completed in 1902 she was initially assigned to the Mediterranean Fleet as its flagship. The ship then served with the Channel and Home Fleets from 1907 to 1910, usually as a flagship. From 1910 to 1914, she was in reserve in the Home Fleet.

The London class was a group of five predreadnought battleships built for the British Royal Navy in the late 1890s and early 1900s. The class comprised London, Bulwark, Venerable, Queen, and Prince of Wales. The ships of the London class were very similar to the preceding Formidable class, with the main differences being their armour layout. They were armed with a battery of four 12-inch (305 mm) guns and they had top speed of 18 knots. They are sometimes referred to as being part of the Formidable class due to their similarity, or as being a class of three ships, with the last two forming their own Queen class. The five ships were built between 1898 and 1904 at the Portsmouth, Devonport, and Chatham Dockyards.