In 1738 Edward Richards, an English Quaker, was granted 50 acres of land in the area we know today as Hampstead. The Richardses' family farm was originally called Rattlesnake Ridge. At the time it was located in the Native American Haudenosaunee Nation along an ancient Algonquian-Iroquois trail called the "Patapsco-Conewago (Hanover) Road" by the colonists. Robert Owings and Christopher Gist developed the trail into a public road between 1736 and 1738.
After the end of several conflicts, including clashes with the Native Americans and Pennsylvanians, and the French and Indian War in 1763, the route quickly became heavily traveled by immigrants traveling west and Germans traveling south from Philadelphia. Richards' son-in-law, Christopher Vaughn, formally laid out a town plat in 1786 at a rest stop at a boggy stream crossing called Spring Garden, and named his development Hampstead, after the hometown of the Richards family in England.
The road was known as the Pack Horse Road, or the Wheelbarrow Road after the Maryland General Assembly ordered it widened in 1793. In 1805, it became a toll road when it was incorporated by the Baltimore and Reisterstown Turnpike Company.
As the road improved, the town quickly grew, especially after 1808, when a stage coach company established a freight and passenger stop in town to provide supplies for area farmers and ship farm products to Baltimore. The town incorporated in 1888, shortly after the Western Maryland Railway's Harrisburg Division reached Hampstead in 1879. The fire department was formed shortly after an April 15, 1899 meeting.
Since August 2009, when a bypass was opened to redirect traffic away from Main Street, Hampstead's leaders and citizens have rededicated their commitment to retaining the community's quintessential small-town atmosphere. A state-funded project to revitalize Main Street is expected to begin this summer.