When the phalanx disappeared ?

[Sarcasm]

3 meters or 4 meters, The range of medieval pikes(and by this I mean those of Flanders and Scotland) ranged from 6 to 8 "feet". And yes the Schiltron was not a circular formation, Pez's explanation is exactly why the schiltron couldn't have been a circle)

Concerning its use. At Bannockburn it was used defensively, as the English were foolishly attacking the well positioned Scots, who basically fought off the English who were attacking from two sides. The credit for the success at Bannockburn has to be also given to the non-pike men who were part of the Schiltron. Unlike the Phalanx the Schiltron consisted also of men with all sorts of polearms(as Sarcasm pointed out) and also dismounted men-at-arms(most of the knights and men-at-arms of Scotland dismounted to fought in the Schiltron).

So again the differences between Phalanx and Schiltron are significant.

Right, typo on my part. Less than 4 meters - on the low end of pikes.

Actually it could have been used in a circle. At Falkirk when the schiltrons became isolated, they probably assumed a circular formation and sat on their asses until they were shot to pieces. And at Bannockburn the vanguard probably assumed a similar formation.

Also, the schiltrons did attack the English at the second day of Bannockbrun, they didn't just defend. In fact they pike-pushed the whole English infantry off the field after resisting a mounted knight charge.

[SaberHRE]

Yes, sorry forgot to mention that the Scots did later advance.

However I don't believe that Scots deployed a circular schiltron at Falkirk, because it would make no sense. At Stirling the used regular retangular or square formation, but they were in attack really. At Falkirk a I doubt a circular formation would be employed due to the need for a strong defensive array. But again this is debateable

Just one last thing, Schiltron is often solely attributed as Wallace's creation, whereas people forget about Andrew de Moray, who was an equally brilliant soldier and leader(if not greater than Wallace himself). His guerilla war and minor campaigns against the English in Northern Scotland are pretty impressive. So no doubt de Moray would have largely contributed to the creation of the Schiltron

[pezhetairoi]

I'm not sure about that, based solely on your description of him. He was a minor-campaign and guerrilla leader. You'd hardly find a need to innovate something like the heavy ponderous and above all, defensive, schiltron for what is essentially hit and run fighting.

Moray... if I recall Braveheart (yes I know, sinfully inaccurate movie) they demonised him as the guy who withheld his troops in support at Falkirk hence contributing to Wallace's defeat.

Now, what was he like actually?