As far as copyright is concerned, newspapers are just like any other printed works.
In the United States, any newspaper published prior to 1923 is in the public domain. Newspapers published between 1923 and 1964 may or may not be, depending upon whether their copyright was renewed or whether they are foreign (non-American) papers whose copyright was "restored" when the URAA trade agreement was implemented in the 1990s. Determining U.S. copyright status for printed materials published during this time period can be difficult. But at least 1923 serves as a "bright line" - anything published prior is clearly in the public domain in the U.S.
http://www.dlib.org/dlib/july08/hirtle/07hirtle.html
Outside of the United States, copyright generally endures for either 50 or 70 years after an author's death. However, there may be complications involved depending upon whether a newspaper story was bought from a freelance reporter or whether he/she did it as a "work for hire" on behalf of the newspaper company with which that person was employed. You would have to check the local copyright law in a particular country to be sure.
https://en.wikipedia.org/wiki/List_of_countries'_copyright_lengths
Unfortunately the fact that copyright laws vary from one country to another may make it difficult to market your game internationally. For example, a newspaper article published in 1921 is public domain in the United States, but may remain under copyright in Canada or the European Union. Generally speaking, you cannot assume that *any* newspaper article published in the early 20th century is public domain everywhere in the world.
P.S. Do not automatically assume that newspaper archives which appear online such as those at the Google Newspaper Archive are in the public domain. Many of the newspapers which appear there have been placed online because Google received permission from the copyright holders to do so. They did not give you permission to use their copyrighted material in your video game....though you can certainly approach a copyright owner to ask for permission.
https://news.google.com/newspapers