I am an historian (now retired) studying mobility in early America (1775-1840) using data available in the Revolutionary War pension application files. As you would guess I have at least two points in time and space -- where and when they entered the army or militia (between 1775 and 1783) and where to send the pension payments (1818 or after). In many cases I have even more data -- some moved after getting their pensions and militia veterans were required to answer the question "where have you lived since the revolution?" Most of the geographical information is down to county (sometime township) level and I would like to be able to display it either by state or county. This is complicated by the fact that both states and counties were just being organized in many cases so date (year) sensitive state and county boundry data is important.
I am looking for software that will allow me to display this data (or selected pieces of it) on a map -- hopefully to be able to show the individual moves with point to point lines, even to bundle similar moves with lines sized to reflect the number of moves it depicts.
That's probably more than enough to begin with.