Question:
What was there to prevent a unit of archers from simply sitting back and massacring a pike formation?

Limited ammunition...

Terrain...

Other infantry...

Cavalry...

All of the above as well as:
Armour
Pike charges

Judging from the assumptions that abound about bows, it would be a miracle that anyone would use another weapon.
However, on the battlefield there are numerous factors that mean that with some notable exceptions, bows have been a secondary weapon at best on the medevial battlefield.

Popular oppinion has it that the longbow is efficient out to 250 meters, which is the maximum distance the arrow will travel.
If you ask a modern bowhunter what's the effective range of his fancy compound bow, he will probably tell you well below 50 meters. This beeing the distance at which you can reliably hit a stationary target with time to aim.
While you can lob arrows at the general area of the target, the chance of actually hitting something is slim.

Another factor is that regardless of efficiency, history has shown missile fire very bad at breaking disciplined troops.
Famously, WWI infantry would litterally walk into artillery and machinegun fire.
In WWI this was a terribly bad idea. But the reason it was attempted was that it had worked up until then.
Short of rapid fire rifles and machineguns, missile weapons just will not manage to kill an approaching infantry formation under normal circumstances.

Thus, the archers have no real possibility to hold their ground; They CAN start shooting at 200 meters, but their fire wont be accurate until 75-50 m, at which point they are to close to the enemy to stand and reload.

The same mechanic applies to early handguns, and are the reason that guns where supported by pikes and helbards until the invention of the flintlock, cartridge reloading and the bayonet.

i was under the impression with the English use of the longbow at least, that it was used more or less like the indirect fire weapons of today?
ie, they were used to saturate an area rather than pick out specific targets.

On one side, yes, the English used longbows. On another, yes, they distinguished themselves by using it in massed volleys instead of the dispersed skirmishing favored by most other kinds of archers. But then there are two other things that we must take into account:

1) a massed volley of arrows is valuable not primarily for its destructive physical effect--which is quite slight--but for the effect it makes on the enemy's morale, especially if the enemy's troops are unsteady in the first place. But this didn't always work with confident and/or well-trained troops and in fact we have solid evidence that the French managed to get into hand-to-hand contact with the English men-at-arms in spite of the longbowmen's volleys.

2) what really distinguished English longbowmen from other archers in the period was that they weren't reluctant to join hand-to-hand combat. Most other archers would have yielded ground (i.e. retreated or fled) before a determined advance by heavier troops, but the English longbowmen frequently and consistently joined their men-at-arms in a massive countercharge towards the enemy lines. Look at the article on the Battle of Poitiers in the Features section. They did the same at Agincourt, and even when they lost big time at Patay it was in hand-to-hand fighting--which meant they stayed long enough for Joan of Arc's vanguard to get into hand-to-hand contact with them!

So there. What made the longbowmen unique wasn't just their arrows, but the combination of their massed archery and their willingness to engage in hand-to-hand fighting. First weaken and demoralize the enemy with arrows, and then engage and rout them with shock. The same tactical method was favored by the British infantry in the Napoelonic Wars and the rest of the 19th century.

I think it would be hard to gauge this as the battles where this takes place are few but from those that come to mind it vary in the effect of both weapons on each other. I think they also fulfill seperate functions on the field so not sure the comparison works. Look at Charles the Bold's army and he has both in different positions, one to defend the other. Under a good leader either force could be used well in the medieval period.

Something to add to Lafayette's comments. IN the end the huge number of archers in english army compared to other armies missle arm is vastly different for the most part. add they do melee after unloading it is not a bad deal.

RPM

Cavalry.

Cheers!

Gordon

Didn't longbowmen have a large role in the defeat of the schiltrons (which granted use shorter spears) at Falkirk?

Speaking as a WotR Longbowmen reenactor who's just beginning and thus hardly an authority, from everyone I've talked to and everything (recent) I've read about, the longbow was more of an indirect fire weapon that would aim at areas (ie units) not men, so hitting the pikemen wouldn't be a problem. However pikemen -won't- stand still if they're a well-drilled late medieval pike formation--they'll attack, forcing longbowmen to withdraw (and probably leave significant amounts of ammunition behind) or forcing the bowmen to fight in a rather disadvantaged position. If I remember right Charles the Bold used a significant number of longbowmen in his army, but the Swiss wouldn't keep still--they closed quickly and forced the archers to engage them in hand-to-hand.

Further, longbows aren't that great against well-armoured troops on foot--a jack and maille shirt will resist an arrow far more often then not, particuarly when it's fired from an appreciable range (longbowmen would take up their bills and bucklers before an enemy got point-blank)--that's why English archers wore them so much in the WotR. I remember hearing in every account of the battle of Flodden field I've ever heard that the scottish pikemen were largely unaffected by the English archers because had become so heavily armoured by the early renaisance that they just weren't that vulnerabe to arrows.

There's a bunch of other guys around here that could probably elaborate on what I've said.
-Wilhelm

Charles the Bold's failure against the Swiss is not an indication of the supposed inferiority of archers. Charles had a comprataivley small numbers of archers, whose presence didn't affect the outcome of the battles. A 1000 archers against 500 men would be devastating - 1000 archers against 10 000 men would not be very effective at all.

I think the greatest myth surrounding the bow is its accuracy.

I own a "stickbow" longbow and a fully modern compound bow. The compound bow is accurate out to about 60 yards (some archers can get good groups much further), but that is because it has a rear peep sight and a front post sight, much like a rifle. The longbow is not accurate. Not at 20 yards, not at 50. The best longbow archers at the range, the kind that always give the new guys pointers, cannot group less than 24" at the 20 yard target. With a compound bow, I can group 4" or less at 20 yards. Some rare archers can take a sightless recurve and group under 6" at 20 yards, so I'll assume that English longbowmen could do the same, but that changes rapidly at 40+ yards, and these are stationary targets under relaxed conditions.

Considering that English longbows did not have sights of any kind, it would betoo much to expect that they could reliably hit a moving target at 50 yards.

agreeing HEAVILY with Mikael here.

Who is to question how accurate and/or effective the longbow is without having trained your whole life with it?