See How Your U.S. Congressional District has Changed Over Time

Nov 6, 2018

You might think of Congressional districts as fixed regions in their states, but they actually shift and change over time. In some cases, it’s due to redistricting, or its more partisan version ‘gerrymandering.’

Congressional districts also shift because of the party affiliations of the people who move in and out of them.  A new interactive congressional map recently went 'live', where you can see those shifts over time, all the way back to the very first congress and all the way down to your home district.  

This Interactive Map includes source data as it visually demonstrates how Congressional districts have shifted between 'red' and 'blue' over time.

When you look at a typical map that shows Republican and Democratic congressional districts in the country, it looks like a sea of red, surrounding blue islands.  But this new interactive map digs deeper.  Click on one, drag your curser and you see how its colors have shifted, or have not, every 2 years, over the past two centuries. And it can also tell you why.  

Virginia Tech History Professor Ladale Winling and a team from the Digital Scholarship Lab at the University of Richmond, created an interactive map of U. S. Congressional Districts. It illustrates how the political landscape has changed over time.

“We can know, not only how congressional boundaries have changed, but we can do all kinds of evaluations: Population density, strength of victory, and we can evaluate the process in an overarching comprehensive way.”

Using a relatively new technology known as ‘GIS,’ which stands for Geographical Information Systems, researchers can dig deeper than ever before into what’s really going on beneath the surface the surface in party politics. There’s a back story to that mostly red Congressional map that appears, at first glance, to comprise most of the country.

Here’s how he puts it: "Land doesn’t vote. " He says with tongue in cheek. "When we look at the U.S. as a whole, when we see results from 2016 or 2012, and it looks like most of America is red, that’s in part because these rural areas have geographically large districts, but they may not represent large populations. (At the same time,) Many of the Democratic voters and Representatives are based in these larger cities and metropolitan areas.”

So 'the map is not the territory.'  It's deceiving.  That is until the researchers studied the data, consulting with historians and political experts to write the 'story' of electoral contests.  That's the humanities side of it.  Then they translated it into forms that can be manipulated and explored further.  That's the science part.

Winling and a team of researchers and students pored over all the old handwritten and typed records of American electoral outcomes and analyzed the data they hold, transforming it into information that could be displayed on a computer. The data is contained in what are known as ‘shapefiles’ which allow viewers to visualize their evolution.

This compilation, says  Winling, is the “most accurate, robust, and up-to-date set of election results in existence.”  And the team plans to keep adding to it with each new set of results, like the one that begins this evening in the mid-term elections of 2018.  He hopes people will use the site,so that scholars, journalists and everyone else who is interested can do their own research into the politics of the day.

Check out the interactive  Congressional District website here:  “Electing the House of Representatives, 1840–2016