I rarely initiate wars, and I am rarely prepared for wars because I don't generally build a comprehensive military--I'm a notorius builder. Nonetheless, I still slaughter the AI. DilithiumDad stated the strategy I use (glad to see I'm not alone).
For my military, I simply garrison my cities with a couple of well-promoted defensive units: maybe two per city. Then at my heartland, or on a worrisome border, I park several extra defensive units (if I possess them) and the handful of highly decorated offensive units that survived the barbarian wars. This small cadre of decorated killers become my excursion force that generally survives the rest of the game without injury as I simply upgrade them when I can.
When the AI attacks, I simply survive his initial wave by rotating the defenders from my back cities to the area of his targeted assault. Generally, the AI targets only a single city at a time, very occassionally two. Sometimes the AI will shift their focus from one city to another, but still their SOD and their war effort become fixated on a particular city or geographical region.
I simply maneuver my units to that area and wait them out. In a small number of my older-high production-already well-developed because I'm an unabashed builder-cities I'll begin building a large number of defenders to assist this "survival" period, and a handful of siege units and perhaps a handful of offensive units to augment my excursion force. In the remainder of my cities, of course, I simply continue building...well buildings.
During this "survival" phase I'll watch the AI utilize the WW1 motto for warfare: that is, "Over the top, men; don't mind their machineguns (or archers)!"
Initially, the waves of assaults can be rather frightful, and survival might seem to waver upon a whim of fortune, but assuming the AI doesn't possess a dramatic tech lead, I always hold. This phase can take a long time, perhaps fifty turns.
Eventually, the AI exhausts itself and empties its cities in the assault. By this time, I've usually teched a little bit and found something useful to give me an edge, or, if I was behind to begin with, now I've caught up and achieved parity. At this point, however, the AI threw everything it had at me, and will now simply have two defenders per city, usually of older style units that it didn't upgrade (generally, the AI will send it's advanced units against you and hold it's crappy ones in reserve).
The AI's military is gone. My initially tiny defensive military is now larger than their force.
Now I send forth my small, but deadly excursion force with a handful of siege units and methodically take all his cities with very minimal losses. If I don't have enough siege units, I simply wait until I can build more and move them forward. Of course, while I wait the AI produces more units, but he can no longer concentrate his forces and produce a SOD, and I can pick off his isolated units easily.
In the modern age, warfare gets real easy, and my attack force is mainly Mech Inf that once were macemen and machine guns that are now c4's and c5's. With their rapid movement and high defensive prowess, the AI can't touch them. To unbalance the AI, utterly confuse him, and prevent him from massing, when I counter-invade, I will usually split my sallying force into three or four small cadres that advance towards separate cities. The AI doesn't know how to respond to that, and usually simply makes its new units sit inside its cities, waiting for me to come for him. With each city that falls, his productive ability decreases that much, while mine continues to grow.
But this phase of the war doesn't take long, the AI collapses rather quickly and will soon accept my offer to become my obedient vassal.
Last week I achieved my first Monarch win in a way that surprised me. I was trying to win space-race, but at the end of the game began falling behind the Mayans in the tech race who also built the Mining corp which gave them a production advantage for the spaceship. I was playing on a huge, inland-sea map (yeah, something different) at marathon speed. The reason I fell behind, unfortunately resulted from the annoying interrupting invasions of aggressive war-mongering civs. I kept defeating their attacks and making peace so I could build, but they kept coming back for more. My disadvantage this game was that my civ was small (only 5 cities) and boxed in so I could not simultaneously both build and fight.
At any rate, China (the largest and most powerful nation) obligated me to warfare. After about 200 turns of warfare, I finally decided I was prepared to take over their civilization. As I marched through his empire, his eastern neighbors, Russia, the Natives and the Carthiginians decided they wanted in on the slaughter. After taking the rich cities I desired. I made peace with China and watched the other civs dismantle him.
To my surprise, he came begging to me to become my vassal. I deigned to become his protector, yet to my horror, I watched both Russia and Carthage each bring SOD's of over 100 units to my newly acquired eastward possessions.
Well, to make a long story short. I survived their onslaughts made peace and built and teched like mad. But, 3 turns before finishing my spaceship, the Mayans launched. They were on the other side of the sea with hostile civs in between me and them. But, I performed a marvelous feat. In the next 29 turns, I turned 6 civs into my vassals.
Now remember, my military is still small, and all of my opponents possess mech infantry and jets and everything else. My strategy was brilliant.
When I invaded each civ, I used my main dummy force to draw the attention of their SOD. I would dig that force in somewhere, and watch the AI slaughter themselves trying to destroy it. A few turns later, after all their forces concentrated on my dummy, I sent in small excursion forces behind their SOD that gobbled up their cities, forcing them to capitulate within 5 or 6 turns. Then I would simply use their railroads to take me to the next civ, and do the same. I must say, airlifts are a powerful thing.
I conquered the world in 30 turns.
It was rather remarkable, in about 200 turns. I went from a peaceful builder with 5 cities (I only had 3 until 1000 AD), to conquering the world, and I didnt even intend to. I never thought that would happen. I'm not even a fighter.
For my military, I simply garrison my cities with a couple of well-promoted defensive units: maybe two per city. Then at my heartland, or on a worrisome border, I park several extra defensive units (if I possess them) and the handful of highly decorated offensive units that survived the barbarian wars. This small cadre of decorated killers become my excursion force that generally survives the rest of the game without injury as I simply upgrade them when I can.
When the AI attacks, I simply survive his initial wave by rotating the defenders from my back cities to the area of his targeted assault. Generally, the AI targets only a single city at a time, very occassionally two. Sometimes the AI will shift their focus from one city to another, but still their SOD and their war effort become fixated on a particular city or geographical region.
I simply maneuver my units to that area and wait them out. In a small number of my older-high production-already well-developed because I'm an unabashed builder-cities I'll begin building a large number of defenders to assist this "survival" period, and a handful of siege units and perhaps a handful of offensive units to augment my excursion force. In the remainder of my cities, of course, I simply continue building...well buildings.

During this "survival" phase I'll watch the AI utilize the WW1 motto for warfare: that is, "Over the top, men; don't mind their machineguns (or archers)!"
Initially, the waves of assaults can be rather frightful, and survival might seem to waver upon a whim of fortune, but assuming the AI doesn't possess a dramatic tech lead, I always hold. This phase can take a long time, perhaps fifty turns.
Eventually, the AI exhausts itself and empties its cities in the assault. By this time, I've usually teched a little bit and found something useful to give me an edge, or, if I was behind to begin with, now I've caught up and achieved parity. At this point, however, the AI threw everything it had at me, and will now simply have two defenders per city, usually of older style units that it didn't upgrade (generally, the AI will send it's advanced units against you and hold it's crappy ones in reserve).
The AI's military is gone. My initially tiny defensive military is now larger than their force.
Now I send forth my small, but deadly excursion force with a handful of siege units and methodically take all his cities with very minimal losses. If I don't have enough siege units, I simply wait until I can build more and move them forward. Of course, while I wait the AI produces more units, but he can no longer concentrate his forces and produce a SOD, and I can pick off his isolated units easily.
In the modern age, warfare gets real easy, and my attack force is mainly Mech Inf that once were macemen and machine guns that are now c4's and c5's. With their rapid movement and high defensive prowess, the AI can't touch them. To unbalance the AI, utterly confuse him, and prevent him from massing, when I counter-invade, I will usually split my sallying force into three or four small cadres that advance towards separate cities. The AI doesn't know how to respond to that, and usually simply makes its new units sit inside its cities, waiting for me to come for him. With each city that falls, his productive ability decreases that much, while mine continues to grow.
But this phase of the war doesn't take long, the AI collapses rather quickly and will soon accept my offer to become my obedient vassal.
Last week I achieved my first Monarch win in a way that surprised me. I was trying to win space-race, but at the end of the game began falling behind the Mayans in the tech race who also built the Mining corp which gave them a production advantage for the spaceship. I was playing on a huge, inland-sea map (yeah, something different) at marathon speed. The reason I fell behind, unfortunately resulted from the annoying interrupting invasions of aggressive war-mongering civs. I kept defeating their attacks and making peace so I could build, but they kept coming back for more. My disadvantage this game was that my civ was small (only 5 cities) and boxed in so I could not simultaneously both build and fight.
At any rate, China (the largest and most powerful nation) obligated me to warfare. After about 200 turns of warfare, I finally decided I was prepared to take over their civilization. As I marched through his empire, his eastern neighbors, Russia, the Natives and the Carthiginians decided they wanted in on the slaughter. After taking the rich cities I desired. I made peace with China and watched the other civs dismantle him.
To my surprise, he came begging to me to become my vassal. I deigned to become his protector, yet to my horror, I watched both Russia and Carthage each bring SOD's of over 100 units to my newly acquired eastward possessions.
Well, to make a long story short. I survived their onslaughts made peace and built and teched like mad. But, 3 turns before finishing my spaceship, the Mayans launched. They were on the other side of the sea with hostile civs in between me and them. But, I performed a marvelous feat. In the next 29 turns, I turned 6 civs into my vassals.
Now remember, my military is still small, and all of my opponents possess mech infantry and jets and everything else. My strategy was brilliant.
When I invaded each civ, I used my main dummy force to draw the attention of their SOD. I would dig that force in somewhere, and watch the AI slaughter themselves trying to destroy it. A few turns later, after all their forces concentrated on my dummy, I sent in small excursion forces behind their SOD that gobbled up their cities, forcing them to capitulate within 5 or 6 turns. Then I would simply use their railroads to take me to the next civ, and do the same. I must say, airlifts are a powerful thing.
I conquered the world in 30 turns.
It was rather remarkable, in about 200 turns. I went from a peaceful builder with 5 cities (I only had 3 until 1000 AD), to conquering the world, and I didnt even intend to. I never thought that would happen. I'm not even a fighter.