I prefer the maps in Wikimedia Commons - there are some amateur maps, which may be even better than some lifted from expired-copyright atlases.
There are quite a few different historical maps of the same year/region - it is very important to have them side by side, because history is very subjective and historical maps are only a subjective and deficient in data representations of historical presence.
- Bavaria is shown to be a Austrian possession in 1800, which is incorrect. Consider the implications if Bavaria was a part of Austria for a while - would there be a Southern German nation? Or would be in fact inconsiderable that Austria is a separate state given the overlap with other German states? If you have only this map as a teaching tool you are implicitly giving a false impression of history.
- There are no Ukrainian states or predecessors (the Cossack Sich) after the 14th century on any of these maps. By omitting this state the appearance of Ukraine seems mysterious in 20th century and a key narrative in the histories of Poland, Russia and even Sweden (the winter war) simply disappears.
There are quite a few different historical maps of the same year/region - it is very important to have them side by side, because history is very subjective and historical maps are only a subjective and deficient in data representations of historical presence.
Maps (by century): http://commons.wikimedia.org/wiki/Category:Maps_by_century_s...