This post is not about romantic dating, but chronological dating. It’s not about the Aztec culture, but about The Aztecs, the Doctor Who story.

(A story I watched while pursuing my epic attempt to watch all Doctor Who during 2013.  (follow along on twitter: https://twitter.com/WatchingDrWho =)

Within the story, Barbara identifies the body of the ancient high priest Yetaxa as having died around 1430, as all the tomb bling around him is from the Aztec “early period” (Aztec empire formed from an aliance in 1427). She confirms that Aztecs were a specialty of hers – which presumably is why she immediately robs the grave for a shiny new bracelet!

Apart from that though, the story is undated.
http://tardis.wikia.com/wiki/15th_century – list the Doctor and Companion’s visit as “Unknown date”.

The novelisation, for what it’s worth, dates it to 1507.

But I was wondering… can we date the episode more accurately than that, from other plot elements?

I think so…

Since the story climax revolves(sic) around a total solar eclipse, can we use that? Well, yes, but only if we know when eclipses occured over the Aztec empire. This, it turns out, is relatively easy.

The Aztec empire at its maximum extent is shown here – 1519 being the year that the Spaniards landed.
http://en.wikipedia.org/wiki/File:Aztec_Empire_1519_map-fr.svg

This version mostly agrees on the outline, and also provides a bit of info about when each area fell under Aztec jurisdiction.
http://commons.wikimedia.org/wiki/File:Aztecexpansion.png

So, what about eclipses that crossed that area of the planet, between 1430 and 1519?

Luckily, NASA has an eclipse page with lots of historical eclipses calculated.
http://eclipse.gsfc.nasa.gov/eclipse.html

So, here are the ones around the end of the empire – from 1501 to 1520:
http://eclipse.gsfc.nasa.gov/SEatlas/SEatlas2/SEatlas1501.GIF
…that’s a bust.

What about earlier? Here’s the 15th century…
http://eclipse.gsfc.nasa.gov/SEatlas/SEatlas2/SEatlas1481.GIF
http://eclipse.gsfc.nasa.gov/SEatlas/SEatlas2/SEatlas1461.GIF
http://eclipse.gsfc.nasa.gov/SEatlas/SEatlas2/SEatlas1441.GIF
http://eclipse.gsfc.nasa.gov/SEatlas/SEatlas2/SEatlas1421.GIF
http://eclipse.gsfc.nasa.gov/SEatlas/SEatlas2/SEatlas1401.GIF

Examining those and comparing, it looks like there were eclipses in 1452, 1477 and 1496 which may fit the bill. So with a bit of screen shooting, gimp and inkscaping, we get an amalgam of map, empire growth, and eclipses…

I’ve included the 1405 eclipse here as it was likely influential to early Aztec culture, but otherwise can be ignored for our purposes. The next one, chronologically, is 1452 – which spanned areas which didn’t fall under Aztec influence until 1486 at the earliest. Similarly,  1477′s eclipse covered area which didn’t become Aztec till 1502. Perhaps these could be argued by someone with more knowledge of the culture of the time (and how it matches known Aztec culture, and what we saw in the episode), but if we trust Barbara’s analysis and stick to a strict “it was actually Aztec” (rather than “soon-to-be-Aztec”) basis here, then that leaves only 1496 – an eclipse which ran across the northern edge of what was, at that time, Aztec controlled land. Indeed, some of which having been Aztec for almost 30 years.

So, 8 August 1496.

Does that settle it then?

Almost… the other factor which should be identifiable and was seen in The Aztecs was the architecture – the pyramid complex itself. And sadly, in my meager searching, I can’t find any sites which had anything like that, in that area…
http://en.wikipedia.org/wiki/Mesoamerican_pyramids

This would perhaps be the most likely location within that eclipse path, if not for the timing – El Tajín fell in the 13th century:
http://en.wikipedia.org/wiki/El_Taj%C3%ADn

So in conclusion? It looks like there really was only one total solar eclipse which fell on the Aztec empire, and that was 1496. The lack of modern knowledge of the city itself can be retconned quite easily, either through natural jungle processes, or by more fictional means (eg: city was razed between then and now by some other alien or supernatural entity).

Otoh, if an appropriate pyramid site can be found within the paths of the 1452 or 1477 eclipses, then that would present a strong argument there – with the retcon required being Barbara being mistaken about her accuracy of location…

Some external links:
http://tardis.wikia.com/wiki/The_Aztecs
http://en.wikipedia.org/wiki/The_Aztecs_(Doctor_Who)
http://tardis.wikia.com/wiki/The_Aztecs_(novelisation)
http://www.drwhoguide.com/who_f.htm
http://eclipse.gsfc.nasa.gov/SEcat5/SE1401-1500.html