The greatest musical prodigy since Mozart (some would say he was even greater), Felix Mendelssohn (1809-1847) excelled in everything he did, musical or otherwise, and during his brief life became Europe's most respected and beloved composer. Yet no musician suffered more drastic swings in his posthumous reputation, and as a result Mendelssohn's music was obscured by a host of extra-musical factors: changes in taste, the rise of nationalism, anti-Semitism,...