Williamson County was named for Robert McAlpin Williamson, a veteran of the Battle of San Jacinto. It’s county seat is in Georgetown. Like most of the other counties through which Texas State Highway 95 runs, it lies between the rocky Edwards Plateau to the west and the fertile farmlands of the Blackland Prairies to the east and straddles the Balcones Fault. I-35 runs roughly down the middle of this fault about thirty miles west of Texas State Highway 95.
Williamson County comprises 1,134 square miles, of which 16 are water. Its western portion of undulating, hilly brushlands lies over limestone karst topography that is conducive to caves and springs and holds the important Edwards Aquifer. It has an average elevation of 850 feet above sea level, while to the east, the flatter prairies average 600 feet. The San Gabriel River, which rises to the west in Burnet County, has two main branches before they converge on the eastern side of Georgetown. Is the only major waterway running through the county, but it has two impoundments: One is on the western side of Georgetown that creates Lake Georgetown, and the other is farther downstream, creating Granger Lake, both of which offer recreational possibilities.
Based on archaeological findings at the important Gault Site (in Bell County, just to the north), humans have lived in the region for perhaps 16,000 years, which predates the Clovis Period (about 11,200 years ago). In 1983, while drilling core samples for a new highway near Cedar Park, highway workers discovered skeletal remains that proved to be between 10,000 and 13,000 years old. They belonged to a female who was 5'3" tall and eighteen to thirty years old at the time of her burial. Dubbed "Leanderthal Lady" after the nearby town of Leander, she is one of the oldest and most complete skeletal finds in North America. The place where she was discovered, which the location of an ancient Native American campsite, is now know as the Wilson-Leonard Brushy Creek Site. Other archaic campsites dot the county, though some were covered by water after the creation of Lake Granger.
After the archaic period, the region was occupied by Tonkawas, who worked flint and hunted buffalo. These are the people who often burned the grasslands of the Blackland Prairies to clear brush and improve their buffalo hunting opportunities. Ash from millennia of these fires helped give the prairie soils their characteristic dark color. Eventually, the Tonkawas, who were generally friendly toward the settlers, were joined by Comanches, Lipan Apaches, Kiowas, Yojuane, Tawakoni, and Mayeye Indians.
The earliest European explorations occurred in the late 17th century by Spanish seeking an alternate route to the El Camino Real to the south. The new route, called Camino de Arriba, was the earliest road through the region, and passed along Brushy Creek and the San Gabriel River. In the mid 18th century, the San Xavier Missions were established along the San Gabriel River just to the east in what is now Milam County. San Xavier is the original Spanish name for the San Gabriel River. After Mexico gained independence from Spain, land grants were awarded in the area, but settlement was stymied for a time by Indian raids.
Settlement truly began in Williamson County in 1835, just prior to the Texas Revolution, with the establishment of a military outpost near the headwaters of Brushy Creek. Named for Capt. John J. Tumlinson, Jr., commander of the garrison there, the outpost was abandoned in early 1836 when its troops were sent to fight the Mexican invasion.
Settlement of the area increased in 1838 after Dr. Thomas Kenney and a party of settlers built Kenney’s Fort on Brushy Creek, near the crossing of the Missouri-Kansas-Texas Railroad. Settlement remained slow, however, as frequent Indian raids kept the settlers at bay. Dr. Kenney was one of the casualties of these raids, and many settlers abandoned the region in 1842. However, the Indians were largely driven out by 1846, opening the region to further settlement. Two years later, Williamson County was formally established, named for soldier and prominent judge Robert M. Williamson. That year, the population was a mere 250, but by 1850, it had grown to 1,568. Many of the new settlers hailed from the Southern states, but there also was a strong contingent from Illinois.
Settlers on the east side of the county grew corn, cotton, and wheat and engaged in dairy farming. In the western portion of the county, cattle ranching predominated, but sheep ranching also became important. In the days before railroads spanned the region, the famed Chisholm Trail gave cattle ranchers their most ready means to transport their cattle to stockyards and rail centers in Kansas and Missouri.
As with all of Central Texas, the Civil War and Reconstruction took their economic tolls, resulting in an upswing in violent crime, with outlaws like John Wesley Hardin and Sam Bass preying on the citizens and family feuds taking their own tolls. But the county experienced better times in the latter part of the 19th century with a return to economic stability aided by the introduction of railroads. Initially built to give farmers a means to ship their huge cotton output, the rail lines were soon used by ranchers to transport livestock, ending the dominance of the once-important Chisholm Trail.
During the post-Civil War years, the influx of German, Polish, and Czech immigrants began to swell the population, and by 1880, the county had grown to more than 15,000 residents. Cotton was king, and in Texas, Williamson County was second only to Ellis County in production. With the coming of rail, the town of Taylor sprang up and rapidly became a major shipping point, boasting facilities for ginning cotton and and compressing it into bales.
The building of paved roads in the county began in earnest in the 1930 to accommodate the growing prevalence of automobiles, which then numbered nearly 12,000. It was during this time that portions of State Highway 95 were first developed.
In the 20th century, two major natural disasters struck Williamson County. The first, known as the Thrall Flood, occurred on September 9–10, 1921, when the remnants of an unnamed hurricane moved inland and stalled over the town of Thrall in the eastern portion of the county. Initially, residents welcomed the rain since a summer-long drought had parched the soil. But the rains did not let up, and the soil was too hard and dry to soak up much water, causing heavy runoffs. The storm eventually dropped 39.7 inches over a 36-hour period, 38.2 of which occurred in a single day. This remains the national official rainfall record for a 24-hour period. Streams and rivers throughout the region, including Bell County to the north, quickly swelled and overran their banks, and as the worst of it came in the middle of the night, many residents were trapped by the deluge. The total death toll was 215, with eight-seven in Taylor and another 93 in the rest of the county, making the event the most deadly flood in Texas history.
The second disaster took place on May 27, 1997, when an outbreak of tornados hit the central portion of the county at and near Jarrell. An F-5 tornado completely wiped out the Double Creek Estates neighborhood in Jarrell, killing 27 people, and an F-3 and two F-2s in the area killed three more. The damages totaled $190 million.
Today, due to phenomenal growth, the population of Williamson County stands at a little over half a million, with the majority living in Round Rock. The urbanization has diminished both agriculture and ranching in the region, but both still go on in the rural area. Now, much of the economy is bolstered by high-tech, retail, medical facilities, and higher education.
Williamson County also has two environmentally protected areas on its west side, both home to several endangered species. The Balcones Canyonlands National Wildlife Refuge is partially in western Williamson County, and the Balcones Canyonlands Preserve in Austin overlaps Travis County.
Lists of Recorded Texas Historic Landmarks and locations on the National Register of Historic Places in Williamson County
LIST OF MUSEUMS IN WILLIAMSON COUNTY