This is a sub project of Frederick County, Maryland Which is a sub project of Maryland counties, cities and towns Hyattstown, Maryland was founded in 1798 by Jesse Hyatt, a Frederick County farmer. The western part of Hyattstown is in Frederick County while the eastern part of Hyattstown is in Montgomery County. By 1804 the town had six houses; by 1811 there were 12. Two of Jesse's brothers, El...