For my master’s thesis I’m using ArcMap to create maps based on a large historical dataset. I’m mapping individual movements over long periods of time. I’m struggling to design the database and figure out how I’m going to actually make the maps. Here, I’ve made a basic, scaled-down example of my project. I want to map which counties the individuals are living in, in 1880 and in 1910.

I have a spreadsheet of individual data:

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It gives the county that each individual is living in in each year. There is no spatial data in it, just the names of counties and county ID

Using a file geodatabe, I made a feature classes of county boundaries as polygons:

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Because the boundaries of counties change over the decades, I made one for 1880 and one for 1910. The counties each have a unique id (ID_NUM). I can use this unique ID to join or relate the two tables together.

My question is where do I go from here?

I want to create two maps. Where the individuals are living 1880 and where they are living in 1910.

Do I join or relate the individual table to both county tables?

Once the tables are connected somehow, how do I use the symbology of the county maps to show where the individuals are living?

How do I give spatial data to the individuals based on the spatial data from the county tables?

I don’t know exactly how to ask for what I need. I’m just at the start of this project and I’m feeling overwhelmed in how to design it.

I am looking to find out the number of individuals living in each county at each time period. Sort of like a population density map

  • 1
    This seems like two separate questions: 1) The design question, of what should the final maps look like. 2) The technical, nuts-and-bolts question about how to achieve the desired final look. If you split this into two separate posts, you'll get more helpful answers to each question.
    – csk
    May 17, 2018 at 16:32
  • There are lots of videos on youtube that can help with this.
    – Simon.y
    May 17, 2018 at 16:48
  • The "How do I give spatial data to the individuals based on the spatial data from the county tables?" makes me wonder what you are trying to answer/show with your map. Do you want each individual to have a spatial location? Or do you want to show the total number of people living in each county? I think you have a good start, but agree with csk that this needs to be broken down into multi questions. May 17, 2018 at 17:39
  • You should think about a choropleth map. Based on what data you have shown, you could make one map for 1880 counties and one for 1910 counties and use the names as color values for both. Then, you can visualize and report differences.
    – gisdude
    May 17, 2018 at 17:39
  • or do it by population change (%) hub.arcgis.com/items/2364f955008145a5ac181dcdab92ad0c
    – Mapperz
    May 17, 2018 at 18:06

1 Answer 1


If you are only interested in counts, then you can just perform a Summarize on the 1880 residence county field in the individual data table. This will produce a table of unique counties and a count of records (individuals) for each county. Then, join the summarized table to your 1880 counties feature class. Symbolize using graduated colors to create a choropleth map (e.g. darker colors = more people). Repeat for 1910.

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