Using Migration Theory to find Ancestors and Immigrants

A common complaint amongst genealogists is an individual who is “missing” in a census or other document in which they “should” appear. And it doesn't help that America is a really, really big place – these people, theoretically, could be anywhere.

Michael P. Conzen, a geography professor, provides strategies for finding "missing" ancestors in his article “Local Migration Systems in Nineteenth-Century Iowa.” In this piece, Conzen explores the migration fields in Iowa using the 1895 Iowa State census. A migration field is simply the area from which a destination draws its migrants. Since ancestors and immigrants move, learning about migration fields can help you find the people whom you seek.

What Conzen uncovered in Iowa is that many people moved along the rivers and later west along the railroad lines. In fact the connection between westward movement and the railroad was so strong, he basically said it wasn’t worth talking about. He also found that the larger the city, the larger the migration field.

On the ground, this means smaller cities in Eastern Iowa, like Keokuk, sent plenty of migrants westward and only pulled in-migrants from a few surrounding counties. The two largest cities, Sioux City and Dubuque, pulled people from all over the state. In Ohio, where I do much research, Wellsville, on the Ohio River, would only pull from a small surrounding area. On the other hand, Cincinnati and later Cleveland, would draw people from a larger area. Similar patterns are seen in Great Britain.

How might Conzen’s study help you find your missing ancestor or immigrant? For starters if you're trying to figure out where someone was before look eastwards. If you are looking for where they went next, always look westwards. Yes, Americans did move move in both directions, but the general trend was an east-west migration. 

Follow the major transportation networks: rivers, turnpikes, canals, and eventually, the railroads. I suppose migrants could have gone orienteering with a map and a compass to reach their destination, but it’s not very likely. 

If your ancestor or immigrant is located in a small town in one census but not in the previous one, check all the surrounding counties in an expanding radius. If they are in a large town, follow the same procedure, but with bigger radiating circles. Basically, it is more likely that your ancestor would have moved, for example, from Brush Creek Township in Jefferson County, Ohio to either of the sizable towns of Wellsville or Steubenville than to have moved from Cleveland to Brush Creek Township.

*****

Conzen, Michael P. “Local Migration Systems in Nineteenth-Century Iowa,” Geographical Review, vol. 64, no. 3, (Jul 1974), pp. 339-361. Stable URL from JSTOR is here, which provides access to the first page unless you have subscription to JSTOR. You may be able to access JSTOR through your local library.

nb. An earlier version of this post first appeared on the Historian's Family in March 2012 as "Have Your American Ancestors Done a Disappearing Act?"