Berne Convention, is an international agreement governing copyright,

https://en.wikipedia.org/wiki/Berne_Convention

Some clippings of page / interesting bits:

The Berne Convention was developed at the instigation of Victor Hugo of the Association Littéraire et Artistique Internationale. Thus it was influenced by the French "right of the author" (droit d'auteur),
which contrasts with the Anglo-Saxon concept of "copyright" which only dealt with economic concerns...

In Kernel v. Mosley (2011), a U.S. court "concluded that a work created outside of the United States, uploaded in Australia and owned by a company registered in Finland was nonetheless a U.S. work by virtue of its being published online".
However other U.S. courts in similar situations have reached different conclusions, e.g. Håkan Moberg v. 33T LLC (2009). The matter of determining the country of origin for digital publication remains a topic of controversy among law academics as well.

A 2009 decision of a Delaware Federal District Court) held that the protections of the Berne Convention are supposed to essentially be "frictionless", meaning no registration requirements can be imposed on a work from a different Berne member country. This means Berne member countries can require works originating in their own country to be registered and/or deposited, but cannot require these formalities of works from other Berne member countries.

In the Internet age, unrestricted publication online may be considered publication in every sufficiently internet-connected jurisdiction in the world. It is not clear what this may mean for determining "country of origin".

If the author is unknown because for example the author was deliberately anonymous or worked under a pseudonym, the Convention provides for a term of 50 years after publication ("after the work has been lawfully made available to the public"). However, if the identity of the author becomes known, the copyright term for known authors (50 years after death) applies.

SOUNDS VERY... ERR MESSY / POLITICAL / SUBJECTIVE
COPYRIGHT COULD GO WHEREVER THEY CHOOSE OR HAS TOO MANY RULES!

CREATIVE COMMONS MIGHT BE A GOOD IDEA / BETTER CHOICE PERHAPS (I'm still learning):

http://freeschool.0id.org/creative-commons-for-this-website/