[dhosek]

Until 1978, copyrights in the US were for 28 years with a 28 year extension. In 1978 there was a new law that aligned things more with copyright in other countries which were generally 75 years or death of the author + 50 years, whichever came later. The US did not retroactively apply the death of the author term to pre-1978 works while other countries did (IIRC in some countries, works that had fallen into the public domain were returned to copyrighted status with the 1978 treaties). Terms have been extended since then so I think in most of Europe it's death + 70 years or 95 years for pre-1978 works while in the US, pre-1978 works are 95 years, but I'm doing all this from memory and probably have plenty of mistakes.