This boundary file contains historic census Block boundaries for which the U.S. Census Bureau tabulated data and was produced by the Minnesota Population Center as part of the National Historical Geographic Information System (NHGIS) Continuation project. The NHGIS is an National Science Foundation-sponsored project (Grant No. BCS0648045) to supplement the digital spatial-temporal database created during NHGIS. The available shapefiles on the NHGIS site represent version 2.0 of historical US boundary files representing various geographic entities for the 1790-2000 censuses. These electronic census boundary files were created from TIGER 2000 UA file. The boundary files have been checked against currently available historical census aggregate data.