In 1772, three Quaker brothers from Bucks County, Pennsylvania chose the picturesque wilderness up river from Elk Ridge Landing to establish a flour mill. John, Andrew and Joseph Ellicott founded Ellicott City which became one of the greatest milling and manufacturing towns in the East.

The Ellicott brothers helped revolutionize the area farming. They persuaded farmers to plant wheat instead of tobacco and introduced fertilizer to revitalize the depleted soil. Charles Carroll, a signer of the Declaration of Independence, was an early influential convert from tobacco to wheat.

The Ellicotts made significant contributions to the area and the era. They built roads, bridges and a wharf in Baltimore, introduced the wagon brake and plaster as a fertilizer, erected iron works, a furnace, rolling mills, schools, a meeting house, stores and houses made from beautiful granite.
In 1791, Andrew Ellicott was commissioned to survey the boundaries for the nation's new capital, Washington, D.C. He was joined by a free black man and family friend named Benjamin Banneker. Banneker worked closely with the city designer, L'Enfant. When the Frenchman abandoned the project and returned home, Banneker was able to recreate the designer's plans from memory.

By 1861, Ellicott's Mills was a prosperous farming and manufacturing area, one of the greatest milling and manufacturing towns in the east. In 1867, a city charter was secured and the name was changed to Ellicott City. The only chartered city in the county, Ellicott City lost its charter in 1935 and was designated an historic district by the county in 1973 and today serves as the county seat.

Howard County was very active during the Civil War. The B&O Railroad and the National Road, which ran through the middle of Ellicott City, transported goods for both sides! The railroad and its bridges became prime targets of the Confederate Army. A contingent of Union soldiers were strategically stationed in the Elkridge area to guard the Thomas Viaduct.