The county was created on September 10, 1784, out of land originally part of Philadelphia County. It is believed to have been either named in honor of Richard Montgomery, an American Revolutionary War general killed in 1775 while attempting to capture Quebec City, Canada, or for the Welsh county of Montgomeryshire (which was named after one of William the Conqueror's main counselors, Roger de Montgomerie), as it was part of the Welsh Tract -- an area of Pennsylvania settled by Quakers from Wales. Early histories of the county indicate the origin of the county's name as uncertain.
Montgomery County is a suburban county northwest of Philadelphia. It is part of the Delaware Valley and marks the region's northern border with the Lehigh Valley region of the state.
It is the 20th wealthiest county in the country (measured by personal per-capita income) and was named the 9th Best Place to Raise a Family by Forbes