County (ICPSR code)
1850: Both samples
1860: All three samples
COUNTY identifies the holding's county of enumeration using the Inter-University Consortium for Political and Social Research (ICPSR) coding scheme. With STATEICP, COUNTY allows the IPUMS data to be merged with ICPSR county-level data. The variable also identifies areas that were not part of any county, including the independent cities of Virginia. COUNTY is a state-dependent variable; it must be read with one of the STATE variables to distinguish between counties located in different states.
Note that many county boundaries and some county names changed over time. The creation of new counties is a further difficulty, especially in more recently settled states. All counties listed have the boundaries that they had in 1850 and 1860; the boundaries could be different in any other year.