There is one problem with super-senses: we don't have the brain for it. Our vision centers are gigantic as is; we'd need to increase computation density in the brain if we wanted three senses to be that well-supported, or increase the brain size.
No modified human can live on modern Mars. They could, however, live on a Mars with low levels of 02 (about half of our partial pressure) and very high levels of CO2, and without additional radiation screening. How do we get there? Gengineer a lichen to live on the modern surface, and produce...
I assume you mean that it would have this relation initially; given Christianity's performance OTL, if it continues the parallel it will end up with a much larger and less consistent body of law, a much less accessible clergy, and a variety of complicating dogmatic schisms.
If you've got enough in the way of optics to make this thing, then you've got enough to use it to make optical lenses from glass. This means A) vision correction, B) telescopes. While A is not so important for world history, B gets you revolutionary thinking about astronomy.
It could even have very similar circumstances: a war fought with weapons more deadly than was realized, because of alliances made in a tangled web, that leaves millions dead and tens of millions longing for revenge. The Balkans still make a good crisis point, though the Caucasus might be just...
While Salamis was crucial, I think in order to have it go the other way you need to prevent it entirely. If Athens does not build its great fleet, or if it uses it to evacuate instead of to offer battle (as was discussed in the Assembly), then Persia can win.
I'd suggest that the famines of the late 1780's would still force a major policy change in France; however, without the expense of funding the Americans, it would be a somewhat gentler crisis. It's entirely possible that the king (or rather, one of his ministers) would appease the bourgeoisie...
I'd suggest that what you really need for early evolutionary theory is not a Darwin, but a Mendel. Darwin's theories required a lot of speculation and drawing together of evidence, which requires a particular mindset in order to receive well. In contrast, if some 6th-century monk had performed...
The fleet under Gylippus would not even have been sent without Alcibiades' defection; according to Thucydides, he was the one responsible for convincing the Spartans to go to Syracuse in the first place.
I would suggest that access to Syracuse's wealth, and not losing the massive number of...
Actually, Thermopylae was largely meaningless except as a morale victory. The true decision was made by the fleet at Salamis, and that's not a battle nearly as easily tipped by the winds of fate as was Marathon.
Marathon, definitely. Not that it would have been a huge military defeat, since it wasn't intended as a real invasion, but the OTL occurence gave the Athenians a huge morale boost later on, the absence of which would have completely altered the later Persian war.
Also, any battle can be huge...
There's one way the Masadans could have gotten free, had they desired to do so (which they likely did not): plague in the Roman camp. An outbreak of cholera or dysentery might have made it possible for the Zealots to escape during the middle part of the seige, before the ramp was under...
The English monarchy was deposed by its parliament, but France didn't have a parliament, so that's not going to play. The Church has always been strong there; possibly Richelieu or a successor in a similar vein backs a coup which replaces the Bourbouns with some other royal family, starting a...
I have no trouble whatsoever with people postulating cosmological variations as a primary PoD; however, if it's a secondary PoD, list it as such. Until you can loft things into orbit, no amount of butterflies can alter the path of an asteroid. Want the Tunguska Event to hit downtown Manhattan...
Sadly, that's not entirely true anymore. We've fallen behind in a number of key areas. The one that really bugs me is biotech, where we lag behind South Korea. Even the most ardent Korean nationalist must admit that they haven't been the leading lights of the world, technologically speaking...