 Born in Benalla, Victoria, Waller entered the Royal Australian Naval College at the age of thirteen. After graduating, he served with the Royal Navy (RN) in the closing stages of World War I. Between the wars, he specialised in communications and was posted as signals officer to various British and Australian warships. He gained his first seagoing command in 1937, as captain of HMS Brazen. In September 1939, he took charge of HMAS Stuart and four other obsolete destroyers that together became known as the "Scrap Iron Flotilla". In 1940, these were augmented by other ships to form the 10th Destroyer Flotilla, supporting Allied troops in North Africa.
