The most exciting discovery about “Dido and Aeneas” in the past 30 years was made by the English scholar Bryan White in 2009 and entails a letter written from Aleppo, in present-day Syria. For younger sons, who had little hope of inheriting family lands or wealth under the rule of primogeniture, a seven-year apprenticeship in Aleppo was a path to wealth and position as a merchant trader. Rowland Sherman was one such apprentice. He departed for Aleppo in 1688 and remained there the rest of his life.

A music lover, Sherman brought a harpsichord with him and later arranged for a small organ to follow. On Feb. 15, 1689, about four months after his arrival, he wrote to a merchant in London asking for a complete “account of musical compositions and performances in the town.” Specifically, he wondered if “Harry” had made a harpsichord transcription of the symphony in a masque (an operalike courtly entertainment) he wrote for Priest’s boarding school.

He went on to say that there was “another symphony” in C minor at the beginning of the second part that had a “neat point” of imitation all in eighth notes; he wrote that he would like this one, too, if it had been transcribed for harpsichord.

What a tantalizing letter. The masque performed at Priest’s school seems to refer to “Dido.” The description of the “second symphony” matches the overture of the opera. The first symphony would have been what preceded the long prologue to the opera, the text of which appears in the libretto but the music for which has been lost. The letter seems to confirm that Purcell did originally set this section to music. (As an extra treat, it appears to tell us that Henry Purcell was known to his friends as Harry.)

If indeed the letter does refer to Purcell’s opera, then by working backward to Sherman’s departure from London, the performance at Priest’s school would have occurred toward the end of 1687, placing that performance in the reign of James II. But even accepting that — and the evidence is far from definite — we have no better grip on when the opera was actually written, whether it was first performed at court and, if so, for which monarch: James II or Charles II. Even the date of 1689 for a production at Priest’s school is not necessarily eliminated, but simply downgraded to a subsequent performance, with a newly written epilogue for the occasion.