CS1: Julian\u2013Gregorian uncertainty

Thelma Furness, Viscountess Furness (née Morgan, 23 August 1904 – 29 January 1970), was a mistress of King Edward VIII while he was Prince of Wales. She was supplanted in his affections by Wallis Simpson, for whose sake Edward abdicated, becoming the Duke of Windsor. She was the maternal aunt of the writer, fashion designer, and socialite Gloria Vanderbilt.
During most of Furness's relationship with the Prince of Wales, she was married to British nobleman Marmaduke Furness, 1st Viscount Furness. They married in 1926 and divorced in 1933, the year before Thelma's relationship with the Prince of Wales ended.
Furness's first name was pronounced in Spanish fashion as "TEL-ma".

Colin Glenn Clive (born Clive-Greig; 20 January 1900 – 25 June 1937) was a British stage and screen actor. His most memorable role was Henry Frankenstein, the creator of the monster, in the 1931 film Frankenstein and its 1935 sequel, Bride of Frankenstein.

Georges Guynemer (French pronunciation: [ʒɔʁʒ ɡinmɛːʁ], 24 December 1894 – 11 September 1917 MIA) was the second highest-scoring French fighter ace with 54 victories during World War I, and a French national hero at the time of his death. Guynemer's death was a profound shock to France.

Johnny "The Scotch Wop" Dundee (November 19, 1893 – April 22, 1965) was an American featherweight and the first world junior lightweight champion boxer who fought from 1910 until 1932. He was inducted into the Ring Magazine Hall of Fame in 1957 and the International Boxing Hall of Fame class of 1991.

Jules Charles Toussaint Védrines (29 December 1881 – 21 April 1919) was an early French aviator, notable for being the first pilot to fly at more than 100 mph and for winning the Gordon Bennett Trophy race in 1912.

André Caplet (23 November 1878 – 22 April 1925) was a French composer and conductor of classical music. He was a friend of Claude Debussy and completed the orchestration of several of Debussy's compositions as well as arrangements of several of them for different instruments.

Jacques Jean Lhermitte (English: ) (20 January 1877 – 24 January 1959) was a French neurologist and neuropsychiatrist.

Félix-Henri "Henry" Bataille (4 April 1872, in Nîmes – 2 March 1922, in Rueil-Malmaison) was a French dramatist and poet. His works were popular between 1900 and the start of World War I.
Bataille's parents died when he was young. He attended the École des Beaux-Arts and Académie Julian to study painting, but started writing when he was 14. Henry wrote plays and poems, but after the success of his second play, La Lépreuse, he became a playwright exclusively. Bataille's early works explored the effects of passion on human motivation and how stifling the social conventions of the times could be. For example, Maman Colibri, is about a middle-aged woman's affair with a younger man. Later, Bataille would gravitate towards the theatre of ideas and social drama.
Bataille was also a theorist of subconscious motivation. While he did not use his theories in most of his own works, he influenced later playwrights such as Jean-Jacques Bernard and the "school of silence".

Luisa Tetrazzini (29 June 1871 – 28 April 1940) was an Italian dramatic coloratura soprano of great international fame. Tetrazzini "had a scintillating voice with a brilliant timbre and a range and agility well beyond the norm...". She enjoyed a highly successful operatic and concert career in Europe and America from the 1890s through to the 1920s. Her voice lives on in recordings made from 1904–1920. She wrote a memoir, My Life of Song, in 1921 and a treatise, How to Sing, in 1923. After retirement, she taught voice in her homes in Milan and Rome until her death.

August Karl Gustav Bier (24 November 1861 – 12 March 1949) was a German surgeon. He was the first to perform spinal anesthesia and intravenous regional anesthesia.