The Will of the Senate - out of character thread III

[Lucjan]

Since we're on the topic of the swords vs. spears thing, I have a question maybe somebody could provide a decent answer to.

Besides the clear advantage spears had over cavalry, and keeping men at a distance, and being incredibly cheaper and easier to come by the materials for than swords, why were spears used as the vast bulk of ancient armaments up until the Romans came up with their sword armed heavy infantry? And what caused the development of the sword if spears were so much more favorable?

The only possibility I can see is the need for an infantry unit to close quickly and very closely to the side or rear of a spear armed unit like a phalanx, where the length of the spear would actually be more of a hindrance than a help. Hopefully somebody can clear up my little historical inquiry.

And what is it with CA's rock/paper/scissor outlook on swords anyway? Unless you catch a spear unit by the flank or rear the swords really have no advantage against the spears, but CA seems to glorify them. But the same goes the other way, spears to the flank or rear of a sword unit are devastating.