In some cases, whistleblowers remain maligned for their work even long after their deaths. But time has changed the way we see many of the leaks from years ago.

Stacker chose the top 10 most groundbreaking leaks in history, containing the largest scale of information and the most impactful aftermaths. Their stories are as dramatic and riveting as any spy novel, but anything but fictional. Some of the following leaks uncovered massive amounts of data and some released very little, but shaped wars and the way we view our governments. Whatever secrets they brought to light, these leaks changed history forever.

Ordered chronologically, the leaks take you through how leaking information has changed over almost 200 years, from strictly newspapers to complicated and encrypted computer data. The future of leaking information is bound to be groundbreaking, especially after looking back at what has occurred already.