Spying has existed since early historical societies in the Middle East, China, and southeast Europe. However, spy services are generally a later development, where groups of government individuals and ultimately agencies within government became responsible for external and internal spying. England, one of the first countries to have a formal spy service, greatly professionalized spying and made it one of the birthplaces of what ultimately became modern espionage.
The rise of espionage or spying services could be traced to the Catholic and Protestant conflicts of the 16th and 17th centuries in Europe. In England, there was both a fear of a Catholic invasion and attempt to take the English throne as well as a desire to shape events in Europe, particularly in the Netherlands. Under the reign of Elizabeth I (1558-1603), one of the first official spymasters in English history arose in the figure of Francis Walsingham, who was also the Secretary of State for Elizabeth I. Another key person was William Cecil. Together, these two helped form what was called the Bond of Association, which was a document, and effectively a foundation document, for a network of spies that devoted themselves to the protection Elizabeth I after the Throckmorton Plot..
The Throckmorton Plot was a plot by English Catholics to murder Elizabeth I and place Mary Queen of Scots on the throne (Figure 1). While the plot failed, it made the aides nearest to Elizabeth realize that England would continue to face external threat, in the form of Spain in particular, and internal descent from Catholics who wanted to put a Catholic monarch back in power. What was significant about the Bond of Association is it committed a network of people to ensure any plot against the Protestant monarch would be attacked even if the reigning monarch was killed. This, in effect, put the interest of the Protestant state ahead of any individual, even if that individual had a valid claim to the throne. Any potential killers were to be effectively killed at all costs.