The Freeport vicinity is rich in history. It was a hunting and fishing area for the Karankawa Indians. Later, Brazoria County was the base for Stephen F. Austin in colonizing Texas. Prior to the Civil War, it was the site of major plantations that made use of the Brazos River for importing supplies and exporting agricultural products. Most were abandoned after the war.

Velasco (now Surfside) was a Mexican fort until the Texas War for Independence, after which it became a small beach resort. An inland resort and farm community adopted the name of New Velasco, and became just Velasco after the 1900 storm leveled the old town. Much of the inland city was vacated in that storm, and most of the property became dormant until the Freeport Urban Renewal Agency began acquiring it in the 1960's.

Across the river from Velasco, Freeport was created in 1912 when the Freeport Sulfur Company established a town site and began mining sulfur at Bryan Mound, just to the South.

In 1925 the Navigation District was created by vote, and began the work of diverting the Brazos River from its downstream course. This allowed the dammed lower portion to be dredged to form a dependable deep-sea port.

The present industrial character of the area began forming when The Dow Chemical Company began World War II production facilities nearby, with continual expansion since.

Freeport and Velasco merged by a favorable vote in each city in 1957.

The cities of Lake Jackson, Clute, Richwood and smaller communities formed nearby, and this group took the name Brazosport Area and chose to share a school district, community college, chamber of commerce, hospital and other facilities.