This was one of the most popular songs of the beginning of the Twentieth century, if not THE most popular.
The importance of this song, from both a musical and historical perspective cannot be overstated. Picardy was a historical province of France which contained the Somme battlefields – the scene of some of the fiercest fighting during the First World War.
The song became popular throughout Britain and the US. British soldiers singing it when they enlisted for the Front in France and Flanders. During the First World War, the song sold at a rate of 50,000 copies of the sheet music per month, earning Haydn Wood approximately £10,000 in total (£447,055 in 2018 adjusted for inflation).
Following the war, the singing of the song helped soldiers who were suffering from Shell shock to regain their powers of speech.
And musically, it is a remarkable song - it changes key with effortless grace, and features chords that look forward into the century. Dominant 9ths, 11ths and 13ths.
It was crying out to be arranged for guitar and voice, so I offer my humble attempt.
You might want to have the tab open of the sheet music and follow the exquisite singing of John McCormack. There are a few tiny differences you will notice - also, his version in in Bm/ D major, not Am/ C major as I have presented it here. Also, he hits the "Nessun Dorma B" note near the end - too much to ask for a normal singer to achieve in the mass produced version of the songsheet.