Since humanity first set forth upon the seas, the issue of sovereign control over the oceans has been an ongoing concern. Prior to the 20th century, the oceans had been subject to the freedom of the seas doctrine. This principle, adopted in the 17th century, limited national rights and jurisdiction over a narrow band of water along a nations coast, the rest of the sea being free to all and belonging to none. Nearly a century later, the “cannon-shot” rule became the basis for determining how much of the adjacent oceans were under the jurisdiction of a nation. The cannon-shot rule set forth that a nation controlled a territorial sea as far as a projectile could be fired from a cannon based on shore. In the 18th century this range was approximate three nautical miles. As time progressed, three miles became the widely accepted range for the territorial sea.
Due to the slow pace of technological developments prior to the Industrial Revolution, these simple rules provided effective governance of the world’s oceans. With the technological developments of the mid-19th and early-20th centuries, however, not only did ships become more powerful, but technology allowed humanity to exploit ocean resources that had never before been envisioned. Fishermen, once limited to areas near their own coasts, were now equipped with vessels that could allow them to stay at sea for months at a time and capture fish harvests that were far from their native waters. Virtually unrestrained, fleets from around the world traveled to areas rich in fish-stocks. The lack of restraint on the part of these fishermen resulted in fish stocks around the world being depleted without regard to the stability of their numbers.