- Playfair cipher - Charles Wheatstone
- Bacon's cipher - Sir Francis Bacon
- RSA cipher - Clifford Cocks developed the RSA algorithm at GCHQ, approximately three years before it was independently developed by Rivest, Shamir and Adleman at MIT. The British government were not interested in using Cocks' algorithm, so it was classified until 1998, when it was revealed that he had developed RSA before Rivest et al.
Read more about this topic: British Inventions