In some cases, especially when commanding Confederate forces, you will be outnumbered by your opponent. In a massed attack, the winner would be the one with the most men, so you obviously can't hope to win against superior forces that way. A proper defensive strategy is needed to destroy your opponent quickly before they can react.
Let's say that you are commanding a fair sized force of Confederates. Your Union opponent has many more men than you, but does not possess good defensive territory. By acting quickly, you can turn these odds around and take a stunning victory.
Send out some scouts to find good ground on which you can make your stand. Once you've found the right ground, move your force into position as quick as you can (You never know when the enemy might attack you). Position less men in the areas that you can hold for a long time against superior numbers. In the regions where your defensive line is more vulnerable, place more men to defend it.
This is where it gets good. Set up a trap for your opponent. Take some men out of your line and move them back out of the enemy's line of sight. His scouts will see a large hole in your line, a perfect target in his mind. Take care, however, that you don't make your gap too big, or else your entire plan might come crashing down on you.
If your opponent thinks that this is his golden opportunity, he just might attack prematurely. Even if he does attack when his men are fully ready, your defensive line should hold if you've carefully positioned your men. As his forces march towards the gap in your line, draw him in. Start firing your artillery towards his men there, he will think that you're desperate to stop him and it will only encourage him to continue on. Have some of your reserve move in the general direction, encouraging his belief that victory is in his grasp. As he approaches your line, spring the trap.
Have the men who you pulled out of his sight come charging forward. At the same time, have one or two battalions come up on his flanks as he enters the gap. Also concentrate artillery fire on the area, although you must keep an eye on the other areas of your line as well. The attack, if well-coordinated, should catch him off guard. His men should panic and start to break, being fired upon from three sides. If his attack fails, prepare for the next step.
The next phase must be executed at just the right time to succeed. Move to slowly and your opponent will have time to fall back. Move to quickly and your men might be trapped by a premature movement.
After wrecking his attack, your opponent will go on the defensive. Although some of his troops may continue to attack your line, he will most certainly attempt to disengage and regroup before his next move. This is the crucial time to launch your counterattack. Pursue his fleeing men as quick as possible. The moral of his troops will drop and they are fired upon and chased. If you have cavalry in reserve, now is the time to unleash them upon the retreating line. This aggressive attack will only cause more confusion and panic among his men, giving you an advantage over their numbers. Your counterattack must be swift, but make sure that you don't go too far, or you might make a fatal blunder. Make sure that your attack drives them back in confusion, then analyze the situation before either returning to your defensive line, or continuing your attack. If you properly coordinate your men and execute your timing correctly, you can turn the tables on your opponent and take a huge victory.
(Note: This scenario all depends upon the successful trapping of the main enemy assault. This may or may not happen every time, be prepared to adapt to the situation, but remember that a good defensive strategy is to counterattack when your opponent least expects it.)
(Double Note: This is only one of many different ways to defeat a numerically superior opponent. I will post on other tactics in the future.)
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"We will give them the Bayonet!" - Thomas "Stonewall" Jackson