Ijamsville is an unincorporated community located 7 miles (11 km) southeast of Frederick, in Frederick County, Maryland, United States.
In 1785, a Maryland native named Plummer Ijams I moved to Frederick County, having purchased a tract of land called the "Paradise Grant" from the government. His family was originally from Wales, but emigrated to the Anne Arundel region sometime during the 17th century.The land he bought was located approximately 8 miles (13 km) southeast of the city of Frederick and cost Plummer one pound, fifteen shillings, and four pence per acre. Plummer established a plantation on his new land, growing primarily wheat and barley, with a small number of slaves.Plummer I had at least two children: a son named Plummer II, and a younger child named John (born in 1789).In the 1780s and '90s, a number of other settlers (including the Musetter, Montgomery, and Riggs families) established themselves nearby, purchasing land either from the government or directly form the Ijams family. One of the most important were the three brothers John, William, and Thomas Duvall, whose 130-acre (53 ha) tract of land became known as "Duvall's Forest". The Duvalls discovered large deposits of slate in 1800, and two quarries were operational by 1812, at least one owned by a man named Gideon Bantz. Around 1831, the early B&O Railroad asked the Ijams family for permission to construct railroad tracks through its land. Plummer II accepted on the condition that a depot also be built, in part to ease the transport of slate into the local cities. The B&O then christened the heretofore unnamed community "Ijams' Mill and Bantzs' Slate Quarries". On March 13, 1832, four horse-drawn railroad cars travelled through the town on their inaugural journey from Baltimore to Frederick. In 1786, the Ijams family requested that a post office be constructed on their land. This marks the first instance where the region was considered a community, before the arrival of the B&O. The office was finally constructed in 1832, and Plummer II served as its first postmaster. On June 22, 1832, the U.S. Postal Service shortened the town's name to "Ijamsville".