1915 was a peculiar year for Jean Sibelius. It was the year he turned fifty, and also the year he became a grandfather. ‘A strange feeling’, he confessed to his diary. It was made even more strange by the fact that his birthday would be celebrated extremely publicly. By 1915 Sibelius was one of the most famous figures in Finland. In his birthday year, congratulations poured in from admirers across the world, his portrait looked out from Finnish shop windows, honorary banquets were arranged, and the premiere of his Fifth Symphony was set for a public concert on the date of his birthday itself, 8 December.

This might have been oppressive for anyone, but it was especially so for a man already anxious about ageing. Sibelius’s early forties had been dominated by operations for suspected throat cancer, which shocked him into giving up his heavy drinking and smoking — even if only temporarily. He had begun keeping a diary to help stave off his vices. ‘Do not lapse into tobacco and alcohol. Instead, scribble in your “diary”’, he wrote. On the approach to his fiftieth birthday, however, temptation called a little too strongly. He returned, cautiously, to his cigars and alcohol. He simply did not know how to feel about getting older. ‘Every age like every season has its own distinctive feature — please God that I may be wise and prudent and above all new’, he mused. ‘This “uncertainty” penetrates into my bones.’

On top of that, Sibelius was concerned about the status of his music on an international stage. At home in Finland, he had an unassailable position as a “national” figure. Born in 1865, Sibelius’s early years had been defined by the rise of the Finnish nationalist movement. Finland had been a Grand Duchy of Russia since 1809, and throughout the nineteenth century there were increasingly urgent calls for political independence from Russia. Sibelius came of age as a composer at the same time that Finnish nationalists were looking for a cultural figurehead to unite behind. He gave them the sound they were searching for in early works like the choral symphony Kullervo (1892) based on the Finnish national epic the Kalevala, and Finlandia (1899), originally composed for an event protesting Russian press censorship. ‘We recognise these tones as ours, even if we have never heard them as such’, claimed the critic Oskar Merikanto — disregarding the serious debt that Sibelius’s early style owed to Russian influence.