Changes

Modern espionage in England and eventually the United Kingdom has its roots in 16th century Tutor England during a period of great conflict between Catholic and Protestant states. This period produced many plots and internal and external threats that led to the development of the first organized spy networks. These networks increased in their effectiveness in the 17th century as espionage became more professionalized. However, it was the reforms that led to the creation of MI5 and MI6 that has given us modern British espionage. The structure created in the early 20th century has largely stayed in tact, although modifications continue to be made today.