Diverting the inadvertent hijack of this thread, if one were to map the game of Mornington Crescent onto the European monarchies, how would the game be played? And what would it be called?
Ah, it’s been a while since my last game of Æthelred the Unready. Will have to read up on the prior action.
Well, I wasn’t ready for that! 
Given that the topologies are at least equivalent, with the monarchies’ family trees being the more complicated, it would probably work. You’d have to get a map, though. Here’s atext listing to start with–would it even be possible to make a graphical map?
I completly misread the thread title and nearly tore a neck muscle with a double take.
On the subject of which I know the medical types ocasionally play “articular crescent” as a light hearted aide memoir for memorising anatomy. Luftkindt had a delightful matchplay outlined in the september’82 accounts of the Lyme Regis MCS. It caused quite a stir as there were those who were not sure if he was making a serious claim on the validity of the Lewisham Crossover or if he had just over huffed on his chinese pipe. The scholars around this forum will have no trouble discerning his true intent, for me the give away was the tokens played on the future DLR Cutty Sark stop.
I stand by my original suggestion – And I am Marie of Romania
Is Lady Jane Grey in play or is she disqualified by reason that she is not referred to as “Queen Jane”?
As the first subject of one of the Commonwealth Realms to mention it, I get to take 2 tokens, not 1, when the succession of George VI is mentioned in the context of the imperial proclamation of 1931.
Therefore, I play Alexander II, Czar of all the Russias.
At Bethlem Hospital, we found the goal Æthelred to be too easy-to-score. (He married William the Conqueror’s great-aunt, and of course his son Edward III the Confessor can be hit in so many ways.) We switched to Iain Toom Tabard at Bethlem, which leads to thrilling long matches. But I’ll join in a round of Æthelred to warm up. Are we restricted to Christian sovereigns? … or can I play
Alexander II of Epirus
Perkin Warbeck!!
An unusual gambit, I know, but I’d just like to see how well my fellow-players handle the ensuing variations. 
Wait just a second here. The legality of this play depends entirely on which rules we are using, which the OP never explicitly stated. While the Ghent Convention of 1938 (rather unsurprisingly and very parochially) endorsed this play, the Greenwich Rules and the Lancashire Convocation both explicitly outlawed Warbeck. Although there are major differences between the latter rules, they are consistent on this point and they together they command the majority of English-language tournaments.
Making this assumption, I will go back to septimus and play Ashoka the Great.
Phoenix was Queen Of England? What issue was that in?
Definitely. I find that the implicit Christo-centrism of some rulesets definitely impairs play. I mean, we put up with the likes of agnatic primogeniture because it’s in the source material, but that doesn’t mean that we have to be blinkered in the same way.
Alexander the Great. 
Oh dear; Greenwich and Lancashire already invoked. I believe I am still well within the early-game parameters if I stay within the subcontinent and play Aurungzeb.
ETA: Sunspace dropped Alexander in there as I was considering my move; nonetheless I believe Alexander keeps play (barely) within the subcontinent and so my play stands.
Bloody Astonishing X-Men #165
Arungzeb by way of the Peacock Throne lets me play Edward VII of Great Britain with minor punnage withheld.
Oh, nice play, one that gives so many possibilities. I think I will again go eastward, though, to bring us to Tsar Ferdinand of Bulgaria. A minor gambit, I know, but an interesting one, nonetheless.
Oh dear. 3 Alexanders already played, one of them a Romanov; and silenus has already opened up the Edward approach. I apologize for my defensive play but I think things have to be wound back a bit.
Ferdinand I of León and Castile
I’m way out of my depth here – I seek merely to learn from the masters.
A question of theory: Would it now be acceptable to jump the Straits of Gibraltar and play, say, Mohammed V of Morocco? Or would some sort of Borgia gambit be more appropriate?
Oh, a Double Ferdinand. I don’t think that’s been used in official tournament play since Malta, 1954. Reaching back to oldie-but-goodie territory, aren’t we?
Using that as inspiration, I will play Leon II of Abkhazia.
Edit: I see Tierce has beaten me to the punch (or is that “to the putsch”?). I withdraw my play.
Forgive me if I doubt your protestations of inexperience; that’s a very subtle play. If I’m reading the ramifications correctly (and damn this game for forcing me onto the defensive so early) my best defense involves a shift within the Dar al-Islam; I believe Bayezid I (“The Thunderbolt”), closing off the first ten centuries A.H., puts me in a position where a recovery is at least thinkable.
I apologize (slightly) but I can’t resist the golden opportunity, as much as Lazar of Serbia will even further complicate your strategy.
I’ll open with an Arctic Circle variant.
Haakon VII of Norway.