How Brazilian river monitors entered Royal Navy service

Brazil's rubber-price collapse left the completed ships unpaid for at Vickers just as Britain began acquiring foreign orders in 1914. The Admiralty bought them partly to prevent useful foreign-built warships from reaching a possible enemy, even though their unusual design had found no commercial buyer. Their six-inch guns, howitzers, armor, and tiny draft suited river bombardment, while their low freeboard and broad hulls made open-water passages dangerous. Despite poor handling and wet decks, their specialized capabilities helped establish the monitor as a useful wartime type.