When watching movies that take place during the Revolutionary War (e.g. "The Patriot" movie, 2000) the soldiers on each side would line up shoulder to shoulder, load their muskets and then fire at the opposing side.
This seems like a horrible tactic that would maximize casualties. First, are movies that portray open field conflict during this time period accurate in this portrayal? Second, where did this practice originate and why was it used?
If I was the commander of a unit and wanted to engage the enemy, wouldn't using more guerrilla styled tactics be advantageous for my unit? Wouldn't flanking the enemy lines be preferable than just lining up all of my men in one large wall formation as the other side shot at them?
People from the past were not stupid. Here are some reasons why:
Patriotism, or lack thereof: Infantry from the period were not necessarily motivated by love of country. Many of them were conscripts or mercenaries with little connection to their army, and couldn't be trusted to spend a long time out in the field in small units. They were far less likely to take the initiative (and lacked the training to do so) in small groups. Which leads us to:
Command and Control: Before radios it is quite difficult to give commands to men and respond to events on the battlefield. Far easier if you sit on a horse on top of a hill and you can see your men in their columns and lines with their brightly colored uniforms.
Weapons: Were far less accurate than modern firearms. Firing in a mass is more effective, especially because your goal is NOT to kill all of them. Your goal is to break their morale, and getting hit with a giant volley that blows away a large chunk of your line is more devastating to morale than a few plinks here and there. Remember, the muskets are not so accurate and the men are not trained in marksmanship like modern troops. Most of the casualties in battles (even in WW2) would occur after an army routed, wherein they would get run down by fast troops (horsemen in the past, vehicles now) and easily killed/captured.
And in answer to your question, YES, they would try and flank! It's not as easy as it looks, though. Keeping everyone together while moving through difficult terrain full of smoke, fire, dead and wounded men and horses is quite tough. The enemy is also trying to flank you!
If you were a commander and wanted to use guerilla tactics you have to keep in mind:
- Are your men trained in guerilla tactics? Are they equipped for them? Are they motivated to actually seek and destroy the enemy in a coordinated fashion on their own volition, without radios? Because once they disappear into the forest and spread out you are going to have a hell of a time chasing them down to give them new orders. Guerilla tactics work for guerillas because guerillas are usually independently motivated and fight for a 'cause', not necessarily for money or obligation.
As an infantry commander you could form a big square to fend off cavalry, but that puts you at the mercy of artillery. You could spread out to avoid artillery, but that leaves you vulnerable to infantry. You could put your troops in a big line to fight off the infantry, but that (so on and so on). The battles were not simply "line up and shoot" but try to break their line to force a flank and then mop up the rest of the army. Once a few men start panicking and running for their lives while dropping their weapons it can become infectious and destroy a whole army with very few actual deaths.