No, I didn’t discover an ancestor – I wish. I’m just starting out and don’t know much right now about my family history. I discovered this site with a Statistical Atlas of the United States: 1870 with data from the 9th Census of the United States 1870 complete with maps that show population. This appeared on Radical Cartography. When you look closely at the maps and their keys, you can see just how many (or how few) people lived in areas of the United States back in 1870. Always a history lover, I was completely amazed by the maps on the site.