I believe I'm in the process of "losing", though I haven't played it out yet. It's about 1900, and I'm up through mech infantry and some other modern techs. Playing on King, epic, large map, playing as France, and there are two civs that are just insanely huge.
My closest threat is Siam, he's on the same continent with just a small little path to me, but separated by just a tiny body of water on my right(so he lands regularly). Already declared war on me once almost as soon as I got done taking 8 Russian cities. My forces were stretched thing and weakened so I lost 3 cannon and about 5 rifles, and 8 Russian cities. That hurt. A few turns into that war England(on another continent) declared war on me, so I had to shift almost all my naval forces over to my left flank.
After I lost the Russian cities I was able to sue for peace but the England war dragged on from about 1830 until the present(1900), because they won't sue for peace as nothing much has happened(sank a couple of their ships, they pillaged some fishing boats).
I started a couple invasions on a puppeted city state of Engand's, closest to me. First one failed as I didn't send enough(three rifles with ship escort). Second invasion worked out, took the city, liberated it. That's about it though, as they have infantry and anti-tank, anti-air, about 20 units just keep coming, and Ironclads all over(not much against battleship/submarine, but annoying and effective against land units). I only have so many ships so they always get a few hits in, and it's hard to heal up when you keep getting hit.
Pretty soon after that invasion was "successful", Siam declared war on me again and landed a dozen units on my right flank, where I have just a submarine(gifted a destroyer to the city state I liberated) and some infantry. They're also attacking on land through the mountains, where I have a city and infantry.
All in all it's not looking too great, I just can't produce units fast enough and don't have enough. Siam is like a 60 city civ, and England around 50. The game started with 12 civs and we're down to 5 including me(I only eliminated one, very early). Also most of the city states are gone, and started with 20.
This will probably be a loss if they don't sue for peace.
I think the game can be very hard if the "steamroll" happens. By the time I met Siam they had probably 30+ cities, to my 10 or so, and that was a thousand years ago. They get such insane happiness bonuses(or they don't get penalties), that there was not much I could do at that point, too many cities, too many units, even with the bad combat A.I.
Of course I have almost no oil, aluminum or uranium, even though I have a nice chunk of land(about 16 cities and lots of space).
I'm building the Manhattan project, maybe that will help.
