Okay, I realize this has nothing to do with modern day travel. This article is taken from my blog, Crusades and Crusaders. But I figure; heck, why not share it anyway!
“Whoever shall determine upon this holy pilgrimage and shall make his vow to God…shall wear the sign of the cross of the Lord on his forehead, or on his breast. When, having truly fulfilled his vow, he wishes to return, let him place the cross on his back between his shoulders.” That was Pope Urban’s decree in Clermont.
Some historians say that Urban urged the people to wear a red cross. However, it is highly unlikely that every person who took up the cross wore one that was red, especially those laymen and peasants who made the journey. Dying cloth bright colors was very laborious and took several hours to complete. For that reason, merchants sold cloth of such colors at high prices. Only the aristocracy could afford to wear brightly colored clothing.
After making his vow to take up the cross, the Norman Prince, Bohemond of Taranto, took off his expensive cloak and cut it into several pieces, forming every piece into the sign of the cross. He then passed the pieces to his knights and kept one for himself. There is no record of what color exactly Bohemond’s cloak was.
Laymen, peasants and many knights–as was the case with the fictional Father Marc–cut out the sign of the cross from any old blanket or cloak. In fact, many of Peter the Hermit’s followers branded the sign of the cross in their flesh. One priest reportedly engraved the sign of the cross in his flesh and frequently poured acidic fluids in the wound to keep it from healing.
Regardless of its color, the sign of the cross was intended to brand every warrior and pilgrim as a warrior of Christ, or God’s Warrior. Pope Urban did not create a single term to name his cause, nor did he create a name for his followers. It wasn’t until the late twelfth century–around the time of the Third Crusade–that historians founded a term for the Holy Wars: at that time, armed pilgrims were called crucesignatus (one who was signed with the cross). The French later adapted this term into croisade (the way of the cross). The French term was eventually translated into ‘Crusade’ or ‘Crusader’, words that are used today to describe the Holy Wars.