During the Expansionist Era, the first Neutral Zone was declared shortly after two Amercadian Scouts were lost in the vicinity of Barnard’s Star. The last recorded communication from the ship (the Beaver) still echoes, echoes, echoes down the hollow arm of Father Time…

Rongschilde: Sure is quiet…?
Jones: Yeah…too quiet.

By the early days of IER-CO, any slice, hunk, wedge or space of space deemed responsible for three verified disappearances of sentient beings became a lawfully designated Neutral Zone. Verification Recordings, Neutral Zone 8:

1) “It’s amazing! It’s FANTASTIC!!! It’s… it’s…” (static)
2) “I see a… l see… I…” (static)
3) “These reports musta been fakes. This place is as safe as a…” (static)

As the concept of Neutral Zones caught on, some beings found it convenient to augment the ruling to fit other situations. Areas of dispute plagued by border wars (where there was no real profit motive) soon became Neutral Zones, saving wear and tear on the Borderees. This ruling was enforced by Expansionist and, later, IER-CO authorities, in an effort to quiet troubled trade areas. Toward the end of the Stagnation, PAHM Bajar began an experiment using Vercadian Protector Androids to defend the Zones. During the early AnarchEra cycles (when, for all practical purposes, there were no authorities), the incredibly expensive Vercadian Protector Androids became the chief means of enforcing Neutral Zones. If you were rich enough to have a droid, you could have a Zone.