Preludes Nos 05, 06, 017, 20, 24 Opus 51 (1929)

Carl August Nielsen 9 June 1865 – 3 October 1931) was a Danish composer, conductor and violinist, widely recognised as his country's most prominent composer.

All Nielsen's organ works were late compositions, these 29 preludes date from 1929. Nielsen's last major work – Commotio, Op. 58, a 22-minute piece for organ – was composed between June 1930 and February 1931, only a few months before his death.

I found that Carson Cooman had uploaded 5 of these back in 2013 and I thought I would continue his initiative by uploading groups of 5 on a variety of instruments.

This is a good explanation of Nielson's understanding of the organ (from Carson's notes).

While he was composing the pieces, Nielsen was given the keys to Christiansborg Palace Chapel so that he could try out the organ there several times. He also borrowed scores from organist Peter Thomsen, primarily of organ composers of the 17th and 18th centuries, particular Frescobaldi, Scheidt, Scheidemann, Weckmann, and Böhm.

After completing “Commotio,” he wrote in a letter to his son in law: “None of my other works has demanded such great concentration as this: an attempt to reconstitute what is truly the only valid organ style, the polyphonic music that is especially suited to this instrument, which for a long time now has been regarded as a kind of orchestra, which it absolutely is not.”

Considering Nielsen's fame and significant success as a composer of orchestral music, it is interesting that he was attracted to an organ music that drew primarily on baroque models. Nielsen's organ music is not however baroque pastiche, rather it very clearly employs his own personal language, but provides an expression of his frequently stated desire to return to "pure sources." Nielsen's late style was marked by very disciplined and personal kind of neo-classicism, as part of this personal aesthetic decision towards a greater simplicity of expression.