He hosted composers such as Grieg, Elgar, Debussy, Enesco and Grainger at his home in London, and invited them to conduct at the Proms, where major works received their first English performance. Indeed, at the Proms this year, Sir Mark and the Hallé will be performing works by both Elgar and Debussy.
Speyer also introduced the tone poems of Richard Strauss at the Proms. In 1903 he invited Strauss to conduct the first English performance of Ein Heldenleben. Three years later Strauss dedicated his opera Salome ''to my friend Sir Edgar Speyer''. Sir Henry Wood recalled the ''many thousands of pounds' Speyer devoted to make Strauss's Symphonic Poems known to England. However many rehearsals I asked for in order to ensure a perfect performance of a work, he agreed without a murmur. On one occasion - for Strauss's Ein Heldenleben - I had as many as 17.'' Till Eulenspiegel featured under Speyer every year from 1903 to 1914 (and at 102 Proms in all) and will feature on the Last Night of this year's Proms. It's an obvious spot for a tribute to Speyer.
A successful merchant banker, Speyer financed the construction and electrification of the deep-level Tube lines to become ''King of the Underground'' and head of London Transport. He was the key fundraiser for Scott's Antarctic expeditions, a founder and patron of Whitechapel Art Gallery and a major donor to the Poplar and King Edward VII London Hospitals. He was honoured with a baronetcy and a privy councillorship.
However, in August 1914, Speyer was denounced as a German agent by the proprietor of the Queen's Hall, who gave him notice to quit and ended his connection with the Proms. This unleashed a remorseless campaign against him by politicians and the press. Unable to cope with the personal hounding, he, his wife and three young daughters went into exile.
In 1921, Speyer appeared before a judicial tribunal, which found him guilty of disloyalty and of communicating and trading with Germany in wartime. He was stripped of his British citizenship.
In his foreword to my book, Sir Louis Blom-Cooper QC condemns the procedure: ''It reflected no credit on the legal system''. Sir Louis attributes Speyer's ordeal to ''political bigotry, nationalistic hostility and an undercurrent of antisemitism".
There is indeed still much debate over whether he was guilty or innocent - there are factors that point to both. But, a century after these events, Speyer surely deserves credit for his massive contributions to British life? Last autumn, for instance, the Scott-Polar Research Institute in Cambridge put up a commemorative plaque to Speyer. Why not the Proms?
Last Night promenaders joining in Land of Hope and Glory or Parry's Jerusalem and paying homage to the bust of Sir Henry Wood, will probably be unaware that Parry wrote to Speyer to express shame at his treatment, and that Elgar wrote to Speyer to record "the indebtedness of the English people to you" as "a great uplifting force" in British musical life.
In this centenary of Speyer's flight from England, ''is it too much to hope'', wrote Martin Kettle in the Guardian, ''that the evening's conductor will spare a thought for the Proms conductor who was so vindictively treated?'' Radio 3 music presenter Kate Kennedy has called for a statue to be raised in Speyer's honour, to match the bust of Sir Henry Wood.
Lord Black of Brentwood has pleaded in the House of Lords that ''the contribution to music of this man, who was so unfairly treated, is properly recognised with a fitting memorial". He is among those who have called on the BBC to mark the centenary of Speyer's departure with a mention on the Last Night of the Proms.
These calls have so far met with a complete wall of silence from the BBC.
Many of us are left with a compelling conundrum of our own.
Why?
