Entropy Judge
Recurring Bouts of Misanthropy
Alright, so ... the first thing I'm going to do is go through the dragons themselves. Frankly, I don't think they're particularly plausible.
The first issue isn't their size, although that may be one that I'll get to later. No, the big problem is that they're hexapodal. I can't think of a single other animal on Earth that has six limbs; insects and bugs, yes, but no animals or birds. They all have four limbs, and in the case of fliers they're divided into two 'feet' and the 'wings' - which are basically specialized forelimbs/arms, anyway. So the dragons envisaged for the thread are unlikely to have come about biologically, particularly since the dragons appear to follow the traditional fantasy trope of being equally comfortable on the ground or in the air. That is ... difficult to explain biologically. Why should this animal have evolved to have equal facility on the ground and in the air? It is not a sensible arrangement to have evolved naturally - either they would be primarily land-movers, and so lose the wings, or they would be primarily fliers, and so have more standard wings, as with the wyvern-style dragons seen in Skyrim, Reign of Fire, and good old Vermithrax Pejorative. This is because there isn't really much of a benefit to having six limbs and both forms of movement, and biology and evolution tend to do away with things that don't have much benefit. A dragon with two forelimb-wings and two feet is going to be a better flier than a six-limbed dragon; a dragon with no wings and just four legs is going to be able to be bigger and tougher, because it doesn't need to fly. A six-limbed dragon ... can fly and can walk, but it's not going to be very effective and it's going to get out-competed. Related is the way wings work - a four-limbed flier is able to put all that mass in the chest to work on the wings. If you have a six-limbed flier, though, with the wings attaching to the back, you run into problems, because in order to get muscles powerful enough to actually lift it from such a poor place, you need to have a broad, deep back, which means you aren't getting a graceful body and you have to dig into the body's mass anyway and reduce the amount of space for things like lungs and other really important organs, not to mention the front limbs themselves. There are some potential workarounds - some sort of internal lift-gas is a favorite - but then you have to deal with that and how it interacts with the placement of everything else in the body ... and it would help if you explained how the dragon got those lift-gases in the first place.
Now, you want flying dragons, so that puts us in the wyvern-style camp of dragons. Good news is, they're going to be pretty good at flying. Bad news, they're pretty much guaranteed to be pretty damn light and fragile. The largest known flying creature is estimated to have massed up to 250 kilograms, a far cry from the six-ton behemoths you want. This is because flying is hard, and lifting a big, heavy body is even harder, so fliers want to be no heavier than they need to be. A flying dragon would probably not have much in the way of protection - thin scales and no big chunks of bone or anything like that - but they would probably be better at the whole fire-breathing thing than non-flying dragons, because being better at fire-breathing is beneficial to them: a ranged attack option means they don't need heavy protection or claws and they can focus on trying to go fast and/or long. Now, 'better' flames is a broad category, and a lot is going to depend on how fire-breathing works. Which is a bit of a can of worms itself; best option is probably to go the Reign of Fire route and not have them actually breathe fire, but have a pair of chemicals that, when combined with each other and air, burn, and have them spit the chemicals in a liquidy jet. Anyway, 'better' flames would likely be either a larger reservoir or more powerful spitting muscles for better range and/or better control - combining the chemicals at different ranges so the fire starts farther or closer.
Now, terrestrial dragons have their own benefits. First, the Dragon Domestication Project makes a lot more sense for them than it does for fliers - man already has experience taming horses and elephants, so a dragon isn't too much different from what they already know. Flying dragons require a huge paradigm shift in terms of controlling the mount, never mind actually keeping them constrained long enough to actually get them domesticated. Continuing their theme of War Elephant 5.0, terrestrial dragons likely wouldn't have fire-breathing ability, but they would be heavily-armored and probably capable of a surprising turn of speed for short distances. Their biggest drawback, of course, would be food - the larger the animal, the more nutrition it needs, especially if it's going to be doing high-intensity activities regularly.
Anyway, that's 800+ words dealt with. Now to go into some other topics ....
But about those rebellions - depending on how well the Sarmatians do, you could very well be looking at complete Roman withdrawal from those areas. Temporarily, probably, unless the Sarmatians are ridiculously successful. But even temporary freedom from Roman rule would make their return probably troublesome, and if they're weakened sufficiently the Romans may well decide that permanent withdrawal from one or another area is the better choice. A Britain without as much Roman influence, but with a power vacuum for some enterprising warlord to control; or the Jews not being subjected to the Diaspora and loss of their homeland. The butterflies from the latter in particular are literally incalculable - never mind whatever effects on regional politics a Jewish state might have, in the future you don't have as many Jews in Europe, so you don't have the money-lending underclass, you don't have the ghettoes and anti-Semitism, you don't have any of that! Europe is fundamentally altered (I mean, apart from whatever other butterflies get introduced by dragons existing).
And that assumes that there aren't previous butterflies, that Rome expanded where and when it did as in our timeline, while the presence of angry lizards (either stripe!) would probably have altered much more than that by 1 AD. Maybe Julius Caesar is killed by a rampaging dragon that was thought to be subdued when he first visits Britain, or maybe the Teutones don't have the numbers to fight the Romans in 105 BC due to fleeing from marauding dragons, so the Cimbrian War never happens and Marius never rises in power to challenge Sulla so there's no Sullan Civil Wars.
I mean, you are asking about a really complicated scenario, and the 'right answer' is basically "whatever you can reasonably explain." Dragon-riding warlords? Dragons hunted to near-extinction with few changes to history? Something in between? They're all equally valid, it's just a matter of going into the detail on the hows and whys - the important things that explain how people were able to tame or domesticate dragons. Human-dragon interactions before then. Mythology about and worship of dragons. I'm completely serious about 'you could write a book,' because "Earth, but with dragons" isn't exactly an unknown phenomenon. Off the top of my head, the Temeraire series exists, and IIRC it basically just uses "Earth happened, and also there are dragons." Like, Napoleon Bonaparte and George III and Frederick William of Prussia are all characters in the series, so there's basically no changes to society except that there are dragons. It's kept secret that one particular breed of dragon only takes female riders because sexism is exactly the same as it was in reality at that point in time.
The first issue isn't their size, although that may be one that I'll get to later. No, the big problem is that they're hexapodal. I can't think of a single other animal on Earth that has six limbs; insects and bugs, yes, but no animals or birds. They all have four limbs, and in the case of fliers they're divided into two 'feet' and the 'wings' - which are basically specialized forelimbs/arms, anyway. So the dragons envisaged for the thread are unlikely to have come about biologically, particularly since the dragons appear to follow the traditional fantasy trope of being equally comfortable on the ground or in the air. That is ... difficult to explain biologically. Why should this animal have evolved to have equal facility on the ground and in the air? It is not a sensible arrangement to have evolved naturally - either they would be primarily land-movers, and so lose the wings, or they would be primarily fliers, and so have more standard wings, as with the wyvern-style dragons seen in Skyrim, Reign of Fire, and good old Vermithrax Pejorative. This is because there isn't really much of a benefit to having six limbs and both forms of movement, and biology and evolution tend to do away with things that don't have much benefit. A dragon with two forelimb-wings and two feet is going to be a better flier than a six-limbed dragon; a dragon with no wings and just four legs is going to be able to be bigger and tougher, because it doesn't need to fly. A six-limbed dragon ... can fly and can walk, but it's not going to be very effective and it's going to get out-competed. Related is the way wings work - a four-limbed flier is able to put all that mass in the chest to work on the wings. If you have a six-limbed flier, though, with the wings attaching to the back, you run into problems, because in order to get muscles powerful enough to actually lift it from such a poor place, you need to have a broad, deep back, which means you aren't getting a graceful body and you have to dig into the body's mass anyway and reduce the amount of space for things like lungs and other really important organs, not to mention the front limbs themselves. There are some potential workarounds - some sort of internal lift-gas is a favorite - but then you have to deal with that and how it interacts with the placement of everything else in the body ... and it would help if you explained how the dragon got those lift-gases in the first place.
Now, you want flying dragons, so that puts us in the wyvern-style camp of dragons. Good news is, they're going to be pretty good at flying. Bad news, they're pretty much guaranteed to be pretty damn light and fragile. The largest known flying creature is estimated to have massed up to 250 kilograms, a far cry from the six-ton behemoths you want. This is because flying is hard, and lifting a big, heavy body is even harder, so fliers want to be no heavier than they need to be. A flying dragon would probably not have much in the way of protection - thin scales and no big chunks of bone or anything like that - but they would probably be better at the whole fire-breathing thing than non-flying dragons, because being better at fire-breathing is beneficial to them: a ranged attack option means they don't need heavy protection or claws and they can focus on trying to go fast and/or long. Now, 'better' flames is a broad category, and a lot is going to depend on how fire-breathing works. Which is a bit of a can of worms itself; best option is probably to go the Reign of Fire route and not have them actually breathe fire, but have a pair of chemicals that, when combined with each other and air, burn, and have them spit the chemicals in a liquidy jet. Anyway, 'better' flames would likely be either a larger reservoir or more powerful spitting muscles for better range and/or better control - combining the chemicals at different ranges so the fire starts farther or closer.
Now, terrestrial dragons have their own benefits. First, the Dragon Domestication Project makes a lot more sense for them than it does for fliers - man already has experience taming horses and elephants, so a dragon isn't too much different from what they already know. Flying dragons require a huge paradigm shift in terms of controlling the mount, never mind actually keeping them constrained long enough to actually get them domesticated. Continuing their theme of War Elephant 5.0, terrestrial dragons likely wouldn't have fire-breathing ability, but they would be heavily-armored and probably capable of a surprising turn of speed for short distances. Their biggest drawback, of course, would be food - the larger the animal, the more nutrition it needs, especially if it's going to be doing high-intensity activities regularly.
Anyway, that's 800+ words dealt with. Now to go into some other topics ....
Here's a good one, especially since it connects nicely to the topic of religion. So, let's assume that in the mid-to-late 60s AD, an army of Sarmatians reinforced by dragon-riders smashed into the eastern territories of the Roman Empire. In order to see just what would happen, we need to know some things about what's going on in Rome around that time. Fortunately, there's Wikipedia. Hmm ...
But about those rebellions - depending on how well the Sarmatians do, you could very well be looking at complete Roman withdrawal from those areas. Temporarily, probably, unless the Sarmatians are ridiculously successful. But even temporary freedom from Roman rule would make their return probably troublesome, and if they're weakened sufficiently the Romans may well decide that permanent withdrawal from one or another area is the better choice. A Britain without as much Roman influence, but with a power vacuum for some enterprising warlord to control; or the Jews not being subjected to the Diaspora and loss of their homeland. The butterflies from the latter in particular are literally incalculable - never mind whatever effects on regional politics a Jewish state might have, in the future you don't have as many Jews in Europe, so you don't have the money-lending underclass, you don't have the ghettoes and anti-Semitism, you don't have any of that! Europe is fundamentally altered (I mean, apart from whatever other butterflies get introduced by dragons existing).
And that assumes that there aren't previous butterflies, that Rome expanded where and when it did as in our timeline, while the presence of angry lizards (either stripe!) would probably have altered much more than that by 1 AD. Maybe Julius Caesar is killed by a rampaging dragon that was thought to be subdued when he first visits Britain, or maybe the Teutones don't have the numbers to fight the Romans in 105 BC due to fleeing from marauding dragons, so the Cimbrian War never happens and Marius never rises in power to challenge Sulla so there's no Sullan Civil Wars.
I mean, you are asking about a really complicated scenario, and the 'right answer' is basically "whatever you can reasonably explain." Dragon-riding warlords? Dragons hunted to near-extinction with few changes to history? Something in between? They're all equally valid, it's just a matter of going into the detail on the hows and whys - the important things that explain how people were able to tame or domesticate dragons. Human-dragon interactions before then. Mythology about and worship of dragons. I'm completely serious about 'you could write a book,' because "Earth, but with dragons" isn't exactly an unknown phenomenon. Off the top of my head, the Temeraire series exists, and IIRC it basically just uses "Earth happened, and also there are dragons." Like, Napoleon Bonaparte and George III and Frederick William of Prussia are all characters in the series, so there's basically no changes to society except that there are dragons. It's kept secret that one particular breed of dragon only takes female riders because sexism is exactly the same as it was in reality at that point in time.
