Ethel Marian Sumner "Maie" Casey, Baroness Casey, AC, FRSA (née Ryan; 13 March 1892 – 20 January 1983) was an Australian pioneer aviator, poet, librettist, biographer, memoirist and artist. Lord Casey was her husband.
Robert Menzies famously referred to her as "Lady Macbeth".

Early life
Ethel Marian Sumner Ryan was born in 1892, younger child of Victorian-born parents, Sir Charles Snodgrass Ryan, a prominent Melbourne surgeon, and his wife, Alice (née Sumner) Lady Ryan. She is also the granddaughter of Charles Ryan and Marian Cotton (John Cotton's daughter).

She became known as "Maie" at an early age. Rupert Ryan was her brother. She was related by blood or marriage to leading Victorian families; one of her father's sisters married Lord Charles Montagu Douglas Scott, son of the 5th Duke of Buccleuch.

Casey grew up on Collins Street, Melbourne. Her father had his residence and surgery on the same street. Casey was educated privately, and when she was 14 years old she left Australia to attend St George's Boarding School in Ascot, England. After some time she accompanied her brother to Cologne.
Her brother Rupert, a member of the House of Representatives (1940–52), married Lady Rosemary Hay, daughter of the 21st Earl of Erroll. Casey wanted to go to university, but was blocked by her father due to the ill health of the sister of his colleague Sir William Stawell, Florence Melian Stawell, during her time at Cambridge in the 1890s. During World War I, she served as a VAD nurse.
Marriage to Richard Casey
Maie Ryan married Richard Casey on 24 June 1926, at St James's Parish Church, Westminster, London. She supported him in his public life. The couple had two children. His career saw them live successively in Canberra, Washington, Cairo, and India, where, during the last years of the Raj, she was Vicereine of Bengal. In Washington, D.C. she was an eloquent advocate of the United States joining the Allied cause.
Associates
In Egypt, she was a confidante of wartime leaders Winston Churchill, Field-Marshal Lord Montgomery and Harold Macmillan as well as an indefatigable war worker; in Bengal she fought to raise the status of Indian women, discussed political affairs with Mahatma Gandhi and became an intimate friend of Jawaharlal Nehru and Edwina Mountbatten.
Casey also associated with Noël Coward, Patrick White, Katharine Hepburn, Cecil Beaton, Sidney Nolan and Cynthia Reed Nolan.
When in London in 1942, Caroline Haslett threw a lunch for her at the Forum Club with distinguished guests including Lady Cripps and Margaret, Lady Moir. They maintained contact via airmail correspondence and gifts, gave letters of recommendation for international visitors to each other and met up during her visits to the UK. In 1943 she wrote to Haslett "I have a great belief in women, and I believe we should play an increasing part in world affairs. Not only directly; as much by persuasion and influence and by influence as through direct action ... You particularly can and I am sure will influence the women you come into contact with towards active participation in the future, not only in practical deeds but in thought and interest."
Literary works
Casey published three autobiographical works. An Australian Story, 1837–1907, published in 1962 discussed the history of four generations of her family. Tides and Eddies was published in 1966 and an account of her early married life. In 1980, Rare Encounters included the reminiscences of Lady Edwina Mountbatten, Viscount Montgomery of Alamein, Dame Nellie Melba and her mother in law, Evelyn Casey.
Casey also published in 1975 a biography on Nellie Melba entitled Melba Re-visited. She further produced two volumes of verse, Verses in 1963 and From the Night in 1976. She further co-authored Early Melbourne Architecture 1840–1888 in 1953.
Casey further wrote a libretto to Margaret Sutherland's opera The Young Kabbarli.
Interest in the arts
Casey was a painter and illustrator. She attended the Westminster School of Art in London and in Australia associated with the George Bell School in Melbourne. Here she met and became a lifelong friend of fabric designer and artist Frances Mary Burke In 1944, Casey commissioned Burke to create a fashion textile design. It was called "Bengal Tiger" and Casey was photographed by Cecil Beaton wearing the ensemble.
She illustrated Ellis Rowan's 1961's Wild flower Hunter and her own book, An Australian Story.





