In October 1884, an international conference was held in Washington DC for the purpose of fixing a prime meridian and universal day.
The result was the conference agreed the prime meridian (at longitude 0° 0' 00") would be located at Greenwich, United Kingdom.
The conference also agreed Greenwich Mean Time (GMT) would be used as the standard for the world, with the day beginning at midnight at Greenwich and counted on a 24-hour clock.
Read more at BBC News
This was at the height of the British Empire, a great sea-faring nation, so it was not surprising. Imagine if this was on the agenda at the United Nations today. It would be a complete debacle as national egos come into play.