There’s something weird about the world of Robert Jordan’s Wheel of Time. (Weirder than spanking being used as a plot device in The Gathering Storm, I mean.) Readers and fans are used to a Randland-centric view of the planet, which isn’t without merit, since eventually all of the major players in the world gather on that continent to fight the Last Battle against the Dark One.

But that Rand-centric view obscures another avenue of exploration: what exists between Shara and the continent of Seanchan? And why did it prevent the Seanchan from invading east of Randland?

This isn’t something Wheel of Time fans usually wonder about. We don’t even see the Sharans until the last book, and the Seanchan cause so much trouble in the story that I personally didn’t think too much about their home continent. Since the story takes place in Randland (the adopted name of the mapped continent included in all the books), Seanchan and Shara don’t feel like unique cultural entities so much as geographical pincers. In the reader’s mind, we’re constantly trapped between them.

But the Wheel of Time takes place on a globe—on Earth, in fact—and while idly coming across Ellisa Mitchell’s world map I suddenly wondered… how close was Shara to the Seanchan continent? And would it have made sense for Seanchan to invade Randland from the east, instead of the west, as they do in the novels?

It’s a little tricky to figure out. The world map itself is obviously stylized and not meant to provide an exact scale, more of a rough approximation. But it’s the only indicator we have of the size and location of the world’s continents, so it will have to do.

Our quest would be over if the stylized world map was our only resource, but thankfully Jordan himself offers exact land measurements throughout the series. In New Spring, Tar Valon is said to be located exactly 400 leagues north of Tear if you traveled in a straight line. The Wheel of Time Companion has this to add about an ocean voyage between Altara and Illian.

Arran Head: A promontory at the western end of Kabal Deep in southeastern Altara. Between Arran Head and the city of Illian lay a hundred leagues of open water, across the mouth of Kabal Deep. Rand speculated that the Seanchan needed two weeks to reach the border of Illian from Arran Head.

(Oh hi there, sneaky WoT Companion excerpt!) Braem Wood is also roughly noted as being located 50 leagues north of Caemlyn. These three distances are a good mix of both long and short lengths that are large enough to see on the map of Randland. They’re comparable to each other, as well, which allows us to judge the accuracy of the measurements.

Here’s Tar Valon to Tear.

The distance from Arran Head to the coast of Illian should be one-fourth of that. Does it work out?

It actually does! Depending on where a ship lands, it’s 85 to 115 leagues from Arran Head to Illian’s shores. And Arran Head direct to Illian is roughly 100 leagues, as we see above. Half of that red bar should mark the distance of 50 leagues between Caemlyn and Braem Wood.

That also works out! So now we know we have a measurement that can be applied not only to Randland, but the world at large. Let’s see what the distance is between Mayene and the longitude that Falme is at, since those are the most identifiable features on the world map’s version of Randland.

It’s 2.4 times as long from Mayene to Falme longitude as it is from Tar Valon to Tear, meaning that the width of the Randland portion of the continent is 960 leagues. Now that we know that, we can determine how long the entire continent is, from Falme to the eastern coast of Shara.

Looks like the entire western continent is 2.3 times as wide as Randland itself, which means that the continent is 2208 leagues wide. Now it’s Seanchan’s turn on the scale! Even though the Seanchan continent is wider in the southern hemisphere, I’m measuring its width at the same latitude that Falme is at, since that’s where the initial Seanchan forces landed. (i.e. They probably launched from that latitude, as well.) The Aryth Ocean (otherwise known as the World Sea) is enormous, so the Seanchan would have wanted the shortest route possible.

Looks like northern Seanchan is 1.29 times as wide as Randland itself, which means that it’s 1235 leagues wide.

Uh oh.

At first glance, the width of the continents doesn’t seem like a problem, and really they aren’t. But then you need to factor in the width of the Aryth Ocean/World Sea, which is given as 3000 leagues wide in the books. Since Jordan’s given measurements actually agree with each other, we have no reason to believe that his given length of the Aryth Ocean is inaccurate. So in total, the width of the known world from the western shore of Seanchan across to the eastern shore of Shara is 6443 leagues.

And that still isn’t a problem, actually. Until you take into account the length of a league in The Wheel of Time, as stated in The World of The Wheel of Time. In the “Big White Book,” as it is known, author Teresa Patterson gives the length of a league as 4 miles, which would make the distance from west Seanchan across to east Shara 25,772 miles.

The Wheel of Time takes place on Earth, which has an equatorial circumference of 24,901 miles, 871 miles smaller than what we just measured. If a league in The Wheel of Time really is 4 miles long, then Seanchan and Shara should be right on top of each other.

And they’re not, since the Morenal Ocean sits between them.

(Briefly, I wondered if differences in sea level could account for the larger planetary width, but it looks like even if all planetary ice caps melted it would only add 500 feet to the planet’s width. That’s not even close to the 871 mile discrepancy. Plus, the map shows the Earth’s ice caps as present.)

The only way we can fix this discrepancy is by discarding the stated length of Wheel of Time leagues as inaccurate. The “4 mile” length isn’t directly stated by Jordan, but relayed through another author, Patterson, who at DragonCon in 2005 explained that the book contains purposefully vague information in keeping with the “legend fades to myth” nature of the series. In fact, a league has never been measured as 4 miles throughout history. It’s not even measured as 4 miles in the world map itself, as the 3000-mile scale included doesn’t equal a 12,000 mile wide Aryth Ocean.

So let’s propose that a league in the Wheel of Time is actually the same length as a nautical league is measured today: 3.4 miles. This gives us a new length from western Seanchan to eastern Shara of 21,906 miles.

Which means that the final unmapped piece of the world of the Wheel of Time–the Morenal Ocean between Shara and Seanchan–is 2995 miles across.

Now we can make a map that shows ALL the land on Earth during the events of The Wheel of Time.

As we see, the expanse of ocean between Shara and Seanchan is still considerable and explains why the Sharans and the Seanchan probably didn’t interact throughout the history of their cultures. The travel distance is roughly equivalent to the distance between the Azores to the Dominican Republic, a distance that took a leap in ship engineering technology for us to master.

We know that the Seanchan possess that kind of engineering know-how, since they arrive in force across an ocean that’s three times as wide, but its origin is uncertain. There are two possibilities:

The Seanchan’s divided nation and city-states develop this technology on their own and sail east and west. They find Shara first, but instead of a technologically inferior people they find a reclusive united country that is combatitive against foreigners, resulting in the loss of the Seanchan’s explorative fleet, or at the very least a very persuasive argument against spending money and resources attempting a second voyage to Shara. It’s also possible that first contact with Seanchan is what initially motivated Shara to become reclusive and combatitive against foreigners. Even if the Seanchan laid waste to the people, as Cortes did to Mexico, Shara obviously eventually repelled the Seanchan invaders and its culture continued onwards, so the end result is the same whether the Seanchan were destroyed or not upon first contact with Shara. The more likely possibility is that Seanchan did not have their longship technology until it literally arrived in the form of Luthair Hawkwing’s fleet. After all, it took Artur Hawkwing unifying Randland to even get that kind of ship technology developed, and Seanchan wasn’t unified until after Luthair arrived. If this possibility is how Seanchan history played out, then it explains why Seanchan didn’t invade Shara post-Hawkwing, as Luthair’s death set the gaze of Seanchan culture eastward.

That eastward expectation may be the only explanation we have for why Seanchan didn’t cross the much, much smaller Morenal Ocean in order to invade Randland. Even though they would have to go around the horn of Shara, the trip is still about 3000 miles shorter. But hey, Luthair didn’t come from that way and there was no guarantee for the Seanchan that their ships could even reach Randland from that direction. What if there was another land mass between Shara and Randland that extended south and barred the way? Or what if Shara patrolled those seas?

In the end, the answer as to why Seanchan invaded from over the Aryth Ocean is simple: the wheel weaves as the wheel wills. The Seanchan went east because this was the only way Rand could win the Last Battle. If the Seanchan had gone west they would have arrived at Tear before Rand did, meaning Rand may never have managed to obtain Callandor, and we all know how key that item ended up being in the final battle!

It’s a funny world, that Wheel of Time.

Watch for more Wheel of Time Companion and Spin the Wheel coverage through this tag.

Chris Lough writes a lot for Tor.com, you see.