Im trying to design tattoos representing my sons: Alexander, William, and Justin. I'd like to base them on a weapon and helmet from the period and places they represent: Alexander the great, William the conquerer, and Emperor Justinian I. So can yall please assist me with good examples of those?
The Late Roman infantryman that would've served under Justinian wielded either a thrusting spear or a medium-length sword called a Spatha. As /u/Lord_Dog said, the Sarissa was the defining piece of Alexander's armies, but a more 'romantic' weapon would be the kopis, which was a forward-curving short sword typically used as a sidearm. The Norman armies largely used the familiar European one-handed straight sword.
A good example of a weapon from the period of Alexander would be the Sarissa (a pike)