I'm going to have to ask for a little more information here. Do you mean specifically the Greek style Phalanx? Because broadly ever since men had long spears and shields forming up like that was logical. And pikemen formed similar formations in Europe when the pike had it's heyday in the 1700s... But more detail I suppose is what is needed. Essentially, could you expand your question so it's clearer what you specifically would like us to try and put dates on.