Weld County, Colorado was organized as one of the original 17 Colorado counties by the First Territorial Legislature on November 1, 1861.
The county was named for Lewis Ledyard Weld, an attorney and territorial secretary who died while serving in the Union Army during the
Civil War. Its territory once included land that now comprises Logan, Morgan, Phillips, Sedgwick, Washington, and Yuma counties, in
addition to Weld County.
Source: wikipedia.org