The Leander class was a class of eight light cruisers built for the Royal Navy in the early 1930s that saw service in World War II. They were named after mythological figures, and all ships were commissioned between 1933 and 1936. The three ships of the second group were sold to the Royal Australian Navy (RAN) before World War II and renamed after Australian cities.

The York class was the second and final class of heavy cruisers built for the Royal Navy under the terms of the 1922 Washington Naval Treaty. They were essentially a reduced version of the preceding County class, scaled down to enable more cruisers to be built from the limited defence budgets of the late 1920s.