British Gauge War

The Gauge War (or Gauge Wars) was a figurative war of intense competition to control new territory, waged between expanding railway companies in Great Britain in the nineteenth century. The contest for which track gauge should become the standard carried with it the greater struggle for which companies and stakeholders would win or lose in commerce, controlling or commercially dominating rights of way.

The Gauge War was arguably the earliest format war between two similar but incompatible technologies.