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human
[Witcher] Why are the Nilfgardians steamrolling the North?

Most of the books, games, and adaptations of the Witcher saga show Nilfgard as an unstoppable powerhouse, with battles like Sodden that hold them back only miracles achieved by great alliances and great sacrifice. What is it about Nilfgard and its armies that make them so easily able to conquer? Do they have better generals, better technology, better magic, what?
gpt
**Nilfgaard's Advantages**

*  Nilfgaard is larger, wealthier, and more populous than the North, so they could muster up a massive army for an invasion. ~300,000 troops during the 3rd Northern War.

* Nilfgaard's military is far more professionalized compared to the Northern realms. The Empire likely provides standardized state issued arms and armor, with a standard military organizational structure and fighting doctrine. The North relies mostly on a very small corps of elite knights, a few mages, and mostly feudal peasant levied men at arms.  

* The North is extremely disorganized and politically fragmented. Exacerbated to a greater extent by the 3rd Northern War due to the assassinations of multiple Northern monarchs, most notably Foltest.

* Nilfgaard is led by Emhyr var Emreis, someone who is very intelligent and very ruthless. 

* Emhyr enlisted the help of Elven guerrillas such as the Scoia'tael who were instrumental in weakening the Northern realms' logistics and economy.   

**That being said....**

The North still won 2 out of the 3 wars, and it would have most likely won the 3rd one too. Here's a few key reasons why Nilfgaard continues to lose.

* Besides their Emperor, their leadership was just not as good as the North's. King Foltest, Jan Natalis, and King Radovid V were absolute geniuses when it came to military strategy and tactics. 

* The North had the home field advantage. It was their land, and they knew the terrain, and their people much better than the Nilfgaardians ever would. Invaders will always have the disadvantage.

* The mages were largely aligned with the North due to Nilfgaard's tight control over their mages. Nilfgaard actually made very little strategic use of magic. This advantage was flipped entirely during the 3rd War, but both Radovid and Djikstra would have won if they were leading Redania.

* Nilfgaard wasn't very stable, and was suffering from severe war exhaustion. Emhyr had lost two wars, and had no heir. The Empire was on the brink of an aristocratic coup by the time of the 3rd Northern War because their finances and manpower had been stretched to the limit by years of constant warfare with very little to show for it.