Carroll County was created in 1837 from parts of Baltimore and Frederick Counties. It was named for Charles Carroll of Carrollton.
The earliest European settlers in Carroll County were predominantly Pennsylvania Dutch from southeast Pennsylvania and English from the Tidewater region of Maryland. German was the predominant language of Carroll County until the Civil War. German was most heavily spoken in the northern and western parts of the county. The towns of Hampstead, Manchester, and Taneytown had German majorities. English-speakers were a minority and were concentrated in southern Carroll.

These charts show statistics for Carroll County for the following: Median Sale Price, Active Listings. Average Days on Market, Months of Supply. Each chart shows Detached and Attached housing types.