From Ancient Spies to Modern Algorithms

Tracing the History of Surveillance

Can you imagine living during the time of ancient spies and secret communication highways, aka— spyways?

People had to monitor who was in earshot and constantly watch their backs. This wasn’t just about paranoia; it was a reality shaped by the ever-present desire for control.

Spies and informants often conducted surveillance in early human civilization through word-of-mouth or carrier pigeons. Today, it is carried out by computers. No matter the type of communication we invent, someone finds a way to intercept, hack, steal, or lurk, with or without us knowing.

Knowing the history of surveillance and its current methods is the first step to protecting your private information and your rights.

Early Surveillance

For thousands of years, spying was a well-known profession used by powerful people and groups, including monarchs, governments, religious leaders, monks, and more. But why?

Royalty and Spies — Control at the Highest Levels

Spying was vital to maintain control, order, and sometimes safety because those in power, by their very existence, were targets.

Pharaohs employed networks of spies to monitor their vast empires and protect against internal and external threats.

In Medieval Europe, spies helped maintain control of political rivals within their own courts, uncover neighboring kingdoms’ secrets, plan for the demise of enemies, and control subordinates.

Throughout history, spies provided early warnings of plots, rebellions, and invasions and helped people stay in power or gain more control.

Surveillance to Rule Them All: Controlling the Commoners

This is why people outside the ruling elite, mainly enslaved populations or conquered peoples, were closely watched and scrutinized to keep them under control.

In fact, record-keeping through tactics like the annual census was vital across major civilizations to this end. The census gave monarchs an answer to “how many?” — ie: able-bodied men to fight in wars as well as religious, ethnic, or political minorities. Monarchies could then manipulate systems of taxation, land ownership, and other civil codes to punish and reward groups at their discretion.

Wartime Worries for Minorities

During wartime, marginalized groups, such as Japanese Americans during World War II, were subjected to discriminatory surveillance and internment. In Eastern Europe during the same time, Jews, gypsies, and people with mental or physical disabilities were surveilled, persecuted, and mass murdered by governing and military forces.

In the U.S., throughout the 1900s, during the civil rights era and the Cold War, the FBI oversaw the surveillance of civil rights groups that included wiretaps and conducting IRS audits. They collected intel to create lists detailing information about people they arbitrarily deemed a threat to national security.

History frequently repeats itself, especially with centralized authorities and surveillance tactics. When powerful centralized institutions need to exert control, they tell us: “There is a dangerous threat in our midst. The only way you’ll be safe is to give up your privacy.”

Just look at Germany during World War II. In a flash, a free democracy crumbled into a control-obsessed government that surveilled the population in every aspect. From music and fashion to simple conversations with their neighbors, people went from expressing freely to living in fear of their every move being watched, recorded, and punished.

This millennia-long Faustian bargain has been the foundation for how we relate to our own personal privacy. After all, isn’t your privacy a small price to pay for the greater good, as determined by the ruling elite? The question becomes, what happens when they label YOU as the threat?

Surveillance and the Technological Age

Just Telegram It to Me

The development of modern technology, beginning with the telegram, was a game changer in the world of communication as well as surveillance. This bullet train communication pathway changed how information was shared and inevitably intercepted. Telegram messages sent over long distances were easier to monitor, making these coded conversations a prime target for surveillance of people and government officials, especially during wartime.

Ring, Ring — Talk of the Town

The invention of the telephone in the late 19th century made the telegraph look like tin cans with string. In addition to being able to communicate instantly, another surveillance portal was born. Telephones could be tapped, and conversations could be recorded, making it possible to collect a great deal of information about the masses as well as any person of interest.

Screens are Screening You: The Digital Age of Surveillance

The advent of the digital age means everyone has a digital footprint and profile made up of all of their interactions and habits. The everyday tools necessary for moving about in society are the same tools being used to collect a vast amount of information about people, including their physical movements, their communications, and even private thoughts.

There are various forms of digital surveillance, one of which is online tracking. Every move you make on your computer, website, or smartphone can be, and likely is, watched and recorded. Why? Because your data is extremely valuable.

Currently, the global data broker market is valued at $305.32 billion USD in 2025 and expected to grow to $585.48 billion USD by 2034.

Your digital footprint is used to target you with ads and to learn more about your interests. So, the best case scenario is that you find products and services you wouldn’t otherwise discover on your own, but worst case… these ads are actually manipulating your behaviors.

We share information, store information, and agree to Terms of Use quite freely. And yes, data collection can sometimes be innocent. But what happens when details about you fall into the wrong hands? History has shown us that it can be quite threatening in more ways than one.

Trackable search habits, facial recognition, and geolocation are just some valuable personal data you leave behind. But it doesn’t stop at these crumbs of behavioral data — when you upload your photo ID for KYC, send your DNA out for sequencing, or upload tax documents, you’re forced to allow server owners to scoop and sell your information.

Since the dawn of civilization, the everyday person hasn’t had any choice but to obey if they want to participate in society.

And we think that’s bullsh*t.

What if no authority, no matter how big or small could abuse or delete your data? What if your data privacy and ownership was not a privilege, but the default?

For the first time in human history a different choice is possible — thanks to decentralized technologies like Sia.

Welcome to a new era of surveillance — where you can close the blinds and say “no thanks” to powerful companies who’ve insisted there’s no other option.

A different way forward is here. Follow Sia on Bluesky, X, Instagram, and TikTok to learn more about protecting your digital rights.

Thank you to Sabrina Dorfman for contributing to this article.

From Ancient Spies to Modern Algorithms was originally published in The Sia Blog on Medium, where people are continuing the conversation by highlighting and responding to this story.