Lenore Shows Up Late

I sat quietly at my desk until the last of my new students came straggling into the lecture hall to take their seats--the usual two dozen extra-credit scavengers, utterly ignorant as to the precise topic of my course, and only here because of its somewhat arcane title in the course-book:

   The Hidden History of Transylvania, 5 credits--Professor H. Catafalque.

 I stood up as my class sank into their seats and cleared my throat: "Transylvania was once a mighty Empire which dominated all Europa, and the uncannily long-lived Cauchemar dynasty dominated Transylvania," I began, gazing over my spectacles at their blank faces, most of which showed no more enthusiasm for me than I had for them...but I was gratified to see several puzzled frowns as I continued.
 "I don't propose to go into all the details today; I shall merely state the bare facts--in particular, the dates of their reigns.  These alone should suffice to arrest your attention; please bear in mind that the following dates cover only the reigns of these monarchs, not their actual life-spans."
 Without further ado, I proceeded to scrawl the following list up on the blackboard:

                                 THE HOUSE OF CAUCHEMAR

                     Valdemar I, King of Transylvania, AD 771-903
                      Umbriel I, King of Transylvania, AD 903-1019
                       Ligeia, Empress Regnant of Europa, AD 1019-1137
                        Osric, King of Transylvania, AD 1019-1113
           Egaeus, King of Transylvania, AD 1113-1207/Emperor of Europa, AD 1137-1212
                  Valdemar II, King of Transylvania, AD 1207-1299 (fatally deposed)
                   Ligeia, Empress Undead of Europa, AD 1212-1399 (second reign)
             Lumek the Cursed, King of Transylvania, AD 1299-1314 (slain by Ligeia)
            Radu, King of Transylvania, AD 1314-1416/Emperor of Europa, AD 1399-1499
       Valdemar III, King of Transylvania, AD 1416-1522/Emperor of Europa, AD 1499-1522
      Ligeia, Wraith-Queen of Transylvania and Europa, AD 1522-1616 (her final reign)
                      Umbriel II, Emperor of Europa, AD 1616-1724
                      Vulnavia, Empress of Europa, AD 1724-present

As I wrote the dates, I could hear the inevitable murmurs and chortles of surprise and disbelief--one robust male voice remarked, "Is he for real?"
 "I assure you, I am quite real," I replied over my shoulder, and my class fell silent--but as I turned round, I saw three or four hands raised in polite protest.
 "Yes, Mr. Ashton?" I nodded to an undergraduate of one of my colleagues in the History department.
 "Sir, Transylvania was never a kingdom," the freckle-faced youth informed me; "At most, it was a voivodeship of the kingdom of Hungary."
 "Mr. Ashton, what is the name of this course?" I asked, arching my eyebrows (which I have been told is my most intimidating expression)--Ashton muttered, "'The Hidden History of Transylvania'."
 "Then kindly permit me to reveal what is hidden," I squashed him, and turned to the rest: "Before I go on, are there any further queries?"
 A young lady with improbable pink hair raised her hand, her eyes fixed on the list on the blackboard: "You...you wrote Ligeia, Empress Undead of Europa," she stammered, establishing beyond doubt her ability to read.
 "Correct," I nodded. "She was the self-same Ligeia who ruled Europa from the throne of Transylvania, two centuries earlier...and yes, she returned as a Wraith to seize the throne again precisely 123 years later...I presume you are about to question the existence of the Empire of Europa, Mr. Ashton?" I added as the tiresome undergraduate opened his mouth--but before he could protest, the door opened and my ears were assailed by the metallic clip-clop of outrageous footwear.  I turned to confront the latecomer--a slender young woman with boyishly short black hair, clad in a tight black velvet dress of unseemly brevity and shiny black high-heeled boots which went up to her knees!
 "Sorry I'm late," she chirped, blithely waltzing to the nearest empty seat and perching thereupon: "Keep going, I'll catch up!"
 "And who might you be?" I inquired in my frostiest tones.
"Lenore Corbeaux! Pleased to meet you, Professor Catafalque--I loved your book, The Shrines Beneath Stonehenge," she added, her dark blue eyes twinkling as she pre-empted my rebuke.
 "Er, thank you...I trust you will be more punctual in future, Miss Corbeaux? Now, as to the House of Cauchemar's dark influence over Transylvania and beyond..."