In 1914 the Germans were planning the construction of four new Battle cruisers. These mounted 14 inch guns that would outclass Britain's 13.5 inch guns then mounted on her Battle cruisers. To overcome this the British decided to build Battle Cruisers mounting 15 inch guns that would be superior to their German counterparts.

A speed of over 30 knots was required and this meant the hull of the ship needed to be extremely long to fit in the necessary machinery. Unfortunately this pushed the heavy gun turrets to the far ends of the ship creating a great deal of stress amidships. Due to their size the armoured protection of these ships was spread over a wide area, and similar to other Battle cruisers of their time speed was seen to be their primary protection.

During construction however the Battle of the Jutland took place and the limitations of Battle cruisers became apparent (the British losing three: The Queen Mary, Indefatigable and Invincible with most of their crews). The British, realizing the error of having such poorly armoured capital ships, tried to rectify the situation by working another 5000 tons of extra armour into the new ships. This however only reduced the critical weaknesses of the new design, and as the first of the class grew in size her sisters were eventually cancelled.