Thank you to Private Internet Access VPN for sponsoring this video. By clicking my link - https://www.piavpn.com/ourowndevices - you can get 83% off on Private Internet Access! That’s just $2.03 a month, and you also get 4 extra months completely for free! During the American Civil War (1861-65), both the Union and the Confederacy used a variety of codes and ciphers to protect vital communications - with varying degrees of success. In this episode, we look at some of the most common systems used by both sides. 0:00 Introduction 1:26 Private Internet Access VPN Sponsor Segment 3:08 Jefferson Wheel Cipher/M-94 7:42 Difference Between Codes and Ciphers 10:18 Stager Route Cipher 15:24 Confederate Substitution Ciphers 16:39 Vigenere Cipher 18:15 Confederate Cipher Cylinder/Disk 19:40 Cryptanalysis of Vigenere Cipher 22:30 One-Time Pad Ciphers 23:13 Book/Dictionary Codes 24:09 Grille Ciphers 26:41 Outro SOURCES: https://ww2.amstat.org/mam/06/Sauerberg_route-essay.html http://www.c3teachers.org/wp-content/uploads/2016/01/ExplainerCipherintheCivilWar-Final.pdf https://cryptiana.web.fc2.com/code/civilwar0.htm https://www.monticello.org/research-education/thomas-jefferson-encyclopedia/wheel-cipher/ https://www.cryptomuseum.com/crypto/usa/ccd/index.htm https://lincolnconspirators.com/2019/07/26/john-wilkes-booths-confederate-cipher/ https://cryptiana.web.fc2.com/code/civilwar5.htm#SEC2 https://cryptiana.web.fc2.com/code/civilwar4.htm https://cryptiana.web.fc2.com/code/civilwar6.htm