Question: When did Richard Minifie join the main theatre of war during the First World War?

Context paragraphs:
Richard Minifie: Richard Pearman Minifie, (2 February 1898 – 31 March 1969) was an Australian fighter pilot and flying ace of the First World War.  Born in Victoria, he attended Melbourne Church of England Grammar School.  Travelling to the United Kingdom, he enlisted in the Royal Naval Air Service in June 1916.  Accepted for flight training, he completed his instruction in December and joined No. 1 (Naval) Squadron RNAS on the Western Front in January 1917, flying Sopwith Triplanes.  He went on to score seventeen aerial victories on this type of machine throughout the year, becoming both the youngest Australian flying ace of the First World War and No. 1 (Naval) Squadron's highest-scoring ace on the Triplane.  The unit re-equipped with the Sopwith Camel late in 1917, with Minifie going on to achieve a further four victories on the aircraft, raising his final tally to a score of twenty-one aircraft shot down.

Western Front (World War I): The Western Front was the main theatre of war during the First World War.  Following the outbreak of war in August 1914, the German Army opened the Western Front by invading Luxembourg and Belgium, then gaining military control of important industrial regions in France.  The tide of the advance was dramatically turned with the Battle of the Marne.  Following the Race to the Sea, both sides dug in along a meandering line of fortified trenches, stretching from the North Sea to the Swiss frontier with France, which changed little except during early 1917 and in 1918.

Theater am Goetheplatz: The Theater am Goetheplatz , also incorrectly known as the Goethetheater , is the main theatre of the city of Bremen in the north of Germany.  Completed in 1913 in the Neoclassical style, it is located in the cultural district to the east of the old town.  After reconstruction with major extensions after the Second World War, it was fully modernized in 2004.  Since 2005, it has been a listed building.

Friedrich Ehmann: Vizefeldwebel Friedrich Ehmann was a German World War I flying ace credited with eight confirmed aerial victories.  Possibly, two of his victims were enemy aces: Richard Minifie and Robert A. Little, though it cannot be confirmed.  Both survived their respective crashes.

Battle and theatre honours of the Australian Army: The Australian Army and its forerunners have won many battle and theatre honours since its formation.  The first honour given to an Australian unit came prior to Federation and was awarded to forces from the colony of New South Wales, which contributed a small contingent consisting of an infantry battalion, with artillery and support units to take part in the short-lived British campaign against the Dervish revolt in the eastern Sudan in 1885 following the death of General Charles Gordon at Khartoum.  The next conflict that saw Australian units receive battle or theatre honours was the Second Boer War.  Between 1899 and 1901, forces from the six Australian colonies fought alongside each other before being replaced in 1901 by forces of the newly established Australian Army following Federation.  A total of five theatre honours were awarded for service in South Africa, being bestowed upon successor units in the form of honorary banners and distinctions presented in 1904, 1908 and 1911.  Since then, the Australian Army has received honours for fighting during the First World War, the Second World War, the Korean War and the Vietnam War, with the Royal Australian Regiment last being awarded a battle honour in 1994 for the First Battle of Maryang San in Korea.  In 2013 units of Special Operations Command were awarded the battle honour Eastern Shah Wali Kot for their actions in Afghanistan in May and June 2010.  A total of 246 honours have been awarded.

HMS Exmouth (1901): HMS "Exmouth" was a "Duncan"-class pre-dreadnought battleship of the Royal Navy.  "Exmouth" was laid down by Laird Brothers at Birkenhead in August 1899, launched in August 1901 and completed in May 1903.  She served as a flagship for various fleets including the Mediterranean Fleet, the Channel Fleet and the Atlantic Fleet from her commissioning in 1903 until the start of the First World War in 1914.  During this time she underwent several refits, two of which occurred in Malta.  Originally she was to join the 6th Battle Squadron and serve in the Channel Fleet, but this squadron was temporarily disbanded and she joined the 3rd Battle Squadron at Scapa Flow instead.  "Exmouth" was then moved to the newly reformed 6th Squadron in late 1914.  Throughout the First World War "Exmouth" moved between various squadrons before finishing her career in the East Indies Station starting in March 1917.  She performed convoy escort duties in the Indian Ocean between Colombo and Bombay before returning to the United Kingdom, calling at The Cape and Sierra Leone.  She arrived at Devonport in August 1917, and paid off to provide crews for antisubmarine vessels.  "Exmouth" remained in reserve at Devonport until April 1919, and was used as an accommodation ship beginning in January 1918.  She was placed on the sale list in April 1919 and sold for scrapping to Forth Shipbreaking Company on 15 January 1920.

Her Majesty's Theatre: Her Majesty's Theatre is a West End theatre situated on Haymarket in the City of Westminster, London.  The present building was designed by Charles J. Phipps and was constructed in 1897 for actor-manager Herbert Beerbohm Tree, who established the Royal Academy of Dramatic Art at the theatre.  In the early decades of the 20th century, Tree produced spectacular productions of Shakespeare and other classical works, and the theatre hosted premieres by major playwrights such as George Bernard Shaw, J. M. Synge, Noël Coward and J. B. Priestley.  Since the First World War, the wide stage has made the theatre suitable for large-scale musical productions, and the theatre has specialised in hosting musicals.  The theatre has been home to record-setting musical theatre runs, notably the First World War sensation "Chu Chin Chow" and the current production, Andrew Lloyd Webber's "The Phantom of the Opera", which has played continuously at Her Majesty's since 1986.

Mihai Codreanu: Mihai Codreanu (] ; July 25, 1876 – October 23, 1957) was a Romanian poet, particularly noted for his sonnets.  A native and lifelong resident of Iași, he published his first volume of verse in 1901, followed by another two years later that solidified his reputation.  Aside from another book of sonnets in 1914 and two during the 1920s, he authored three highly successful translations of French plays.  He also edited a series of newspapers and wrote widely for an array of literary reviews.  Attracted to the stage from early on, he led and reformed the main theatre in his city for several years after World War I, and during the 1930s presided over the arts school in Iași.  Beginning in 1905, he suffered from an eye disease that soon left him unable to read or write, tasks that he accomplished through intermediaries.

Western Desert Campaign: The Western Desert Campaign (Desert War), took place in the deserts of Egypt and Libya and was the main theatre in the North African Campaign during the Second World War.  The campaign began in September 1940 with the Italian invasion of Egypt; Operation Compass, a British five-day raid in December 1940, led to the destruction of the Italian 10th Army.  Benito Mussolini sought help from Adolf Hitler, who responded with a small German force sent to Tripoli under Directive 22 (11 January).  The German "Afrika Korps" ("Generalleutnant" Erwin Rommel) was under nominal Italian command but Italian dependency on Nazi Germany made it the dominant partner.

European theatre of World War I: Although considerable conflict took place outside Europe, the European theatre was the main theatre of operations during World War I and was where the war began and ended.  During the four years of conflict, battle was joined by armies of unprecedented size equipped with new mechanized technologies, leaving millions dead or wounded.

Supporting paragraphs: Richard Minifie Western Front (World War I)
Answer: January 1917