How do you know all this?
I think it's fair to say that the development levels of the Golden Horde's land in 1444 still should be fairly low (relative to France) due to the disruption of Volga trade brought on by Timur. In the war between Timur and Tokhtamysh, Timurid armies razed Sarai and Astrakhan. Even before that point, I think it would be a bit of an exaggeration to call them the pinnacle of pre-industrial development, but I think that Yerm was being polemical (i.e. overstating or slightly exaggerating his case to emphasize a point) so we shouldn't get caught up on exact phrasing.
Overall though, I have to agree with Yerm that we have good reason to believe that the khans of the Golden Horde were interested in development of their provinces. In particular, they promoted agriculture, cattle breeding, cottage industries, and trade. In EU4 terms, Golden Horde lands would have fairly respectable production development (though I guess some unique Golden Horde national ideas with a trade power or production efficiency bonus could also fit). We have the most information on Kazan, which a couple decades prior to the game's start was part of the Golden Horde's patrimony. I'll start there.
According to Andreas Kappeler, "[T]he Khanate of Kazan did not differ significantly in its economic habits and socio-political organization, and with regard to the level of economic and cultural development, from the Muscovite state" in the early 16th century (
The Russian Empire: A Multi-Ethnic History, pg. 25). We know that Volga Bulgar had a strong agricultural and commercial base before the Mongol conquest, but we also know that despite its sacking, the capital Great Bulgar grew ten times in size between the roughly two hundred year period between 1236 and 1445. Kazan was insignificant before the Mongol conquest but developed into a major city over the same period. While still under rule from Sarai, the city developed several libraries, archives, medreses, and a three-tier agriculture system (among large landowners but not tributary peasants). Moreover, goods "produced by the local economy [furs, leatherwork, shoemaking, jewelry, fish] grew throughout the history of the khanate and contributed to the emergence of Kazan as the most important and commercial center of the Volga basin" by the mid-16th century (Azade-Ayse Rorlich's
The Volga Tatars: A Profile in National Resilience, pg. 30).
Kazan obviously reached the peak of its prosperity after independence from the Golden Horde (1445-1552), but the development did not begin in the 1440s. Whether or not we can prove that the Golden Horde's khans sincerely cared about developing provinces, I think we have to acknowledge that they had in place policies that at least enabled development because it was happening under the khanate's rule. Indeed, Charles Halperin argued that the Golden Horde's commercial policies enriched even Russian principalities (citing the growth of cities, construction of walls and churches, increases in silver left behind in wills, etc.) tied into the Volga trade network even when demographic trends (i.e. the Black Death) were working against urbanization. He wrote that, "There is every reason to believe that the international commerce the Mongols had fostered was a major cause of Russia's new urbanization and economic recovery. [...] By promoting trade for their own benefit, the Mongols, who had ravaged Russia and plunged it into economic depression, made possible Russia's recovery and new growth" in the 15th century (
Russia and the Golden Horde: The Mongol Impact on Medieval Russian History, pg. 83).
Note: Andreas Kappeler, Azade-Ayse Rorlich, and Charles Halperin (along with Michael Khodarkovsky, whom I didn't quote) are pretty much the leading English-language historians of the Volga region (well, Kappeler writes in German and Khodarkovsky in Russian, but all of their stuff gets translated into English pretty quickly).
About the Golden Horde's non-Kazani provinces (the so-called "Lower Volga"), we know less. We know that Sarai was a major city with medreses, caravansarais, and a sophisticated water system (Rorlich, pg. 20). Other than that, we basically have to rely on Leonard Nedashkovskii (an archaeologist and anthropologist from Kazan State University) if we want information easily available in English. Fortunately, a few of his works are available online, like
this one. In it, Nedashkovskii paints a picture highly reminiscent of what we know about the Kazani Khanate: the agricultural system was highly developed, the khans promoted and protected trade, a high amount of currency (likely silver) circulated in the economy due to "small retail trade" (presumably exchange of furs, leatherwork, and other cottage industry goods), and that the economy was built upon agriculture, cattle breeding, cottage industries, and trade. Moreover, he tells us that both urban craft goods and luxury items were obtainable to the rural and nomadic strata of the khanate's society - and importantly, in the Lower Volga, Transcaucasia (i.e. "the south Caucasus" to people outside the field), and the Crimea. In other words, the limited information we have on the economy of the Golden Horde suggests that the policies that fostered economic growth in the Kazani region were not anomalous for the economic policies/practices of the Golden Horde (even if Kazan was less directly ruled). Instead, these policies/practices that facilitated economic development applied to several distinct regions under the khanate's rule.
Anyway, I fear that we are pretty far off topic...
Edited for a typo...
