The Masonic Shriners wear a red hat known as a Fez named after a town in Morocco, where in the 10th Century,
50,000 Christians, including women and children, were brutally murdered by Muslims.

As the streets ran red with the Christians’ blood from the massacre, the Muslims dipped their hats in that blood as a testimony to Allah.

The hat is red.
Red=Blood.

The red Fez symbolizes the slaughter of Christians in that town.