Any recommendations for overcoming this issue? I'm working on a project with the eventual goal of creating a crowdsourced, interactive version of a map just li

Any recommendations for overcoming this issue? I'm working on a project with the eventual goal of creating a crowdsourced, interactive version of a map just like this.[1] We haven't gotten to this point yet (only to the 1930s at the moment), but we will eventually come across this problem. Currently we have "admin" levels (sovereignty > state/republic/colony > region/county > city) but this may be disrupted the further back in time we go. One advantage of having data like this publicly crowdsourced is that a decision on how the information should best be processed and presented can be made by the community and potentially changed over time. (And now my pitch: help us out! We just started building the community but have big plans.[2]) [1] http://atlastory.com/ http://atlastory.com/ [2] http://forum.atlastory.com/ http://forum.atlastory.com/