The Magnolia's limecrete section was built by John Park, a chemist and doctor who experimented with concrete after moving to Seguin in 1846.

[6] Park's work, with his imitators and rivals, led to Seguin having the largest concentration of mid-19th century concrete structures in the United States.

The two-story frame building that now sits atop the large basement, replacing the Campbell cabin, dates from the early 1850s.

It shows graceful Greek Revival symmetry and detailing around the door, and a roof line similar to that of the concrete house known as Sebastopol built 1854–56.

Frederick Law Olmsted passed through Seguin in February 1854, and wrote about the town's many concrete buildings, noting, "The hotel is large and good.

Together they encompassed the years when the Magnolia served as an overnight stop for stagecoaches making their runs from the coastal ports to San Antonio and points west.

The building fell into disrepair, leading Preservation Texas to list it among the state's "Most Endangered Historic Places" in March 2012.

[11] On March 1, 2013, Jim Ghedi and Erin O Wallace-Ghedi purchased the building and have privately funded the restoration bringing it back to its original state.