In the Middle Ages travellers feared bandits. How could you take money from one place to another without losing it? To help, a group of rich warrior monks called the Knights Templar stepped in with their network of castles and invented international banking.
Castles and Ciphers
To send money you gave it to the knight at your nearest castle. They gave you a note saying how much you had given them. You could take the note to a far away castle where the local Knight would swap it back for money.
This did not fully solve the problem though. Bandits could forge notes. The Knights Templar solved the by using ciphers: secret algorithms for scrambling messages that only those with the secret could unscramble. Only the Templars knew the secret of their cipher. This was the start of international banking which still needs ciphers to work today.
The Knights Templar’s Secret
The Templar’s cipher is based on their flag which includes a red cross. It is made of four arrow-head shapes. The Templars created 25 symbols combining triangles and dots, pointing in the four directions of the arrowheads in the cross. Each letter of the alphabet except J was substituted for one of the symbols using an easy to remember pattern.
Fun to do
Here is the message HELLO written out in the Templar’s Cipher. Write a secret message of your own using the cipher.