10 Historical Facts About St. Mary’s County, Maryland

CALIFORNIA, Md. — St. Mary’s County is filled with history, as it was one of the first communities founded in the United States. With Historic St. Mary’s City and interesting community centers like The Town of Leonardtown, there are plenty of fun activities for residents and visitors to enjoy all year round. The BayNet has compiled ten fascinating facts about St. Mary’s County, so here’s what you should know about Southern Maryland’s most historic community.

St. Mary’s County Was Maryland’s First County

If you’re new to Maryland, you might not realize that St. Mary’s County was the first county to be founded in the entire state. Leonard Calvert was the one to found St. Mary’s County in 1637, which is when the title began to show up in historical records, though the land was settled around 1634 when sailors reached St. Clement’s Island.

St. Mary’s City Was Originally The Maryland Capital And Is Now A Museum

St. Mary’s City was originally the capital of Maryland prior to the founding of Annapolis, a fact you might not know if you’re not native to Maryland. Settlers established St. Mary’s City on March 27, 1634, and it now acts as a historic museum where visitors can find out about how the original townspeople lived their everyday lives.

Point Lookout Was A Prisoner Of War Camp During The U.S. Civil War

Point Lookout is one of the most notable state parks in Maryland, but the land was once home to a prisoner of war camp that held Confederate soldiers captured by the Union during the Civil War. Known officially as Camp Hoffman at the time of the war, the camp held thousands of soldiers and is now considered by many locals to be haunted by the soldiers who died while in captivity.

America’s Oldest Sheriff’s Office Resides In St. Mary’s County

The St. Mary’s County Sheriff’s Office is currently known as the oldest operating sheriff’s office in the U.S. because it has been used continuously since 1637. A few locations in Virginia may have had sheriffs earlier, but the St. Mary’s County Sheriff’s Office has the oldest documentation to show when Sheriff James Baldridge took office in the Maryland community.

St. Mary’s County Is An Astronaut Training Ground

St. Mary’s County has an extensive history with aerospace training and technology. The U.S. Naval Test Pilot School at the Naval Air Station Patuxent River has trained many famous astronauts in the past, including Alan Shepard and James Lovell, earning St. Mary’s County a reputation for its contribution to space exploration.

English Catholics Founded St. Mary’s County Due To Persecution

The Calvert family primarily founded St. Mary’s County due to the persecution Catholics faced in England during the 1600s, which restricted both the practice of their faith and participation in English politics. Maryland settlers aimed to create a land free from religious persecution of all kinds, and St. Mary’s County was the settlement that allowed the early Marylanders to spread their mission throughout the region.

St. Mary’s County Has Over 500 Miles Of Shoreline

St. Mary’s County is bordered by a ton of water, much of which is considered part of the Chesapeake Bay, though the Patuxent River and Potomac River create many fractured points that extend the total shoreline. As such, St. Mary’s County has over 500 miles of shoreline, so it would take a long time to traverse if you were to follow it through all of its creeks and wrinkles.

Tobacco Was Once The Cash Crop Of St. Mary’s County

For centuries, tobacco was the “cash crop” that dominated the agricultural land of St. Mary’s County, with farmers beginning to transition to other crops in the 1900s. Maryland’s Tobacco Buyout Program of the early 2000s ended the era, as farmers began to receive payments if they shifted their focus toward alternative plants like vegetables and grains.

An Amish Community Lives In St. Mary’s County

In the 1900s, many Amish families decided to part ways with Lancaster, Pennsylvania, and head to St. Mary’s County. The result of this migration is that hundreds of Amish families live in St. Mary’s County within communities around Charlotte Hall and Mechanicsville. They participate in agriculture and farmers markets, so although Maryland doesn’t have nearly as large an Amish presence compared to Pennsylvania, they’re an important part of the St. Mary’s community today.

The U.S. Oyster Festival Is Held In St. Mary’s County

The St. Mary’s County Fairgrounds hosts the U.S. Oyster Festival each year in Leonardtown. In 2026, the festival is planned for Oct. 17–18, offering a variety of things to do and food to try for a day of family fun. The festival even hosts an Oyster Shucking Championship, allowing experts in the field to show off their skills.

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