Walter Cass saw active service in the Anglo-Boer War, Gallipoli and the Western Front. In addition he spent time in India - on the North West Frontier (modern day Pakistan) - and Egypt, before returning to Australia to take charge of training in the last years of World War 1. This was followed by various military posts in Australia throughout the 1920s. Walter Cass was married in 1916 to the Canadian nurse Helena Holmes. Walter Edmund Hutchinson Cass was born in Albury, New South Wales on 28 August 1876. He became a trainee teacher in 1890. In 1901, he enlisted as Corporal in the 5th Victorian Mounted Rifles Contingent. He served in the Boer War and was promoted to Sergeant. In 1902, he resumed teaching and from 1904 served in the militia as Lieutenant in the 6th Australian Infantry Regiment. He joined the permanent staff of the Australian Military Forces in 1906, serving as Lieutenant in South Australia in 1906-08 and in Western Australia in 1908-10. He was promoted Captain in 1910 and Major in 1913. He served in India in 1911, and in Sydney and Hobart until war broke out. In August 1914, he was appointed Brigade Major of the 2nd Brigade, Australian Imperial Force. In 1915, he served at Gallipoli from April to December, was promoted Lieutenant-Colonel in August and commanded the 2nd Battalion. He was appointed commander of the 54th Battalion in February 1916 and served in northern France at Fleurbaix and Fromelles in July. He was then evacuated to England on medical grounds. He was mentioned in dispatches twice and appointed C.M.G. in 1916. He was demobilized in April 1917 and became Director of Military Training at Australian Military Forces headquarters, Melbourne, in 1917-21, General Staff Officer in Queensland in 1922-23 and Base Commandant in Hobart in 1924. For the next two years he was Director of Organization and Personnel Services at Melbourne, then Base Commandant there in 1926-29 and in Adelaide in 1929-31. He was made temporary Brigadier in December 1929. In September 1931, he returned to Melbourne where he died on 6 November.

Helena Whitney Holmes was born in Truro, Nova Scotia, on 9 July 1886. In 1909, she visited Australia and met Walter Cass in Perth, Western Australia. They corresponded for the next few years. In 1916, she nursed at the Canadian I.O.D.E. Hospital in London, run by the Imperial Order of the Daughters of the Empire. She and Cass married on 18 October, at St James's Anglican Church, Westminster. In 1917, she returned with him to Australia. In 1930, her career as a journalist began in Adelaide where she published her first article in January and gave her first radio talk in October. From 1931 to 1965, her permanent home was in Melbourne where she played an active part in the social life of the city. She acted at The Little Theatre in Melbourne in 1934. In 1936-37, accompanied by her daughter, she toured the United States of America, giving talks about Australia. In 1937, she gave lectures in England about Australia and Australian gardens. She lived in London in 1939. In the 1930s and 1940s, she wrote for Australian, British and Canadian publications, using both her own name and several pseudonyms. Her last radio talks appear to have been given in 1944. She died in Melbourne in 1965.

Angela Laventie Hutchinson Whitney Cass, only child of Walter and Helena Cass, was born on 20 May 1926. She graduated Bachelor of Laws from the University of Melbourne in 1948 and was admitted to the Victorian Bar in 1949. She married broadcaster Timothy Herbert Eric Cousens in 1953.