The Oldest Business in Texas: The Pioneer Flour Mills (October 25, 2025)

by Scott Sosebee

Generally, it’s easy to begin an argument, especially in today’s contentious society, about almost anything. For example, ask the question of whether or not Texas is a southern or a western state and no matter what your answer is you will find someone who will tell you that you are absolutely incorrect. So, I’m not trying to start an argument here, but in my mind I asked myself, “What is the oldest business in Texas that is still operating?” That should be pretty straight-forward, shouldn’t it? Well, guess what? It’s not exactly clear. Some will tell you that the answer to that is Scholz Garten in Austin, which began in 1866. Others say it is the Menger Bar in San Antonio, founded in 1859. But, I am going to fall on the side of another San Antonio commercial institution, C.H. Guenther Flour Mill, also founded in 1859 a few months before the Menger opened. It continues to operate today as Pioneer Mills.

Carl Hilmar (C.H.) Guenther, a German emigrant, founded the Pioneer Flour Mills. Born in March 1826 in Weissenfels, Saxony, Guenther was the third of eight children born into a wealthy family. However, despite the privileges he had, Guenther did not see a future for himself in the Old World, so, to escape an arranged marriage and also to seek out the opportunity that he did not believe was available in Saxony, he decided to leave for the United States in 1848. His parents greatly disapproved of his plans and refused to provide him with any means to travel to or have a stake in the U.S., so Guenther was forced to take a loan through a family friend. He arrived in New York and spent a year working as a laborer before making his way to Wisconsin, where at various times he worked as a day laborer on farms and also in a saw mill.

Everything changed for Guenther in Wisconsin when he was able to open a business as a carpenter. That allowed him to save enough money to leave Wisconsin for Mississippi, where he found good work building cabinets. However, Guenther determined that the constraints of a plantation system that relied on enslaved people as laborers blocked his path to the wealth he wanted, so he first decided, in 1851, that he would likely just go back to Germany. But, before he did so, he wanted to see a place that he had heard about but had never been. A number of men who briefly stopped in Mississippi talked glowingly about opportunity in Texas, so Guenther decided that was where, perhaps, his opportunity lay.

Guenther made his way to San Antonio in 1851. While there he heard about the German town of Fredericksburg, so perhaps a little homesick—in a letter to his parents while he was in Mississippi, he lamented not having heard anyone speaking German in a long while—he bought a new horse and made the trip west from San Antonio to Fredericksburg. After working as a carpenter for a few months, and listening to his customers, he grew intrigued that Fredericksburg did not have a miller or a mill to grind grain, which he determined was vital if a town wanted to grow. He took his savings, along with another loan—this time from his father—and constructed a water-powered mill where Live Oak Creek met the Pedernales River. The first couple of years were good for Guenther, but Fredericksburg was hit by a drought in 1855-1856. The lack of rainfall dried up the creek, and Guenther was forced to close his mill.

Guenther was not deterred and still believed that Texas needed more mills, and San Antonio seemed to him a better prospect. The Alamo city was then the largest city in Texas with a population of over 10,000 and still growing every year. It also had a diverse population with a significant number of ethnic Germans. The San Antonio River was a much larger and better prospect as a power source as well. Once again turning to his father for a loan, in 1859 Guenther bought a prime spot on the river in what is now the King William District—the neighborhood of a number of German immigrants—and built what became the first grain mill in San Antonio. He also built his home on the same tract. He still, however, had a problem. Potential flooding meant that it was a bad idea to build his mill right over the river, but building a house and mill meant that he had depleted his funds and did not have the money left to build a diversion canal to use for power. However, Guenther was once again resourceful. He approached local farmers—most of them Alsatian immigrants who farmed near Castroville—with an idea; if they would help him build a canal, he would promise to buy all the grain they could possibly harvest. Enough said yes and Guenther was in business.

Guenther was an astute businessman who followed a philosophy that Andrew Carnegie would make popular decades later. He constantly sought to upgrade his mill with the latest technology, which would allow him to produce the finest flour. He then sought and secured contracts from Mexican farmers that allowed him to produce flour year-round, and he also had the good fortune—some say through effective lobbying—to have his mill adjacent to a railhead that came through San Antonio. That allowed him to quickly ship flour around the state and without the added cost of shipping that his competitors faced. By the time the Civil War ended, Guenther had built a second mill with steam-powered turbines, which made his capabilities even quicker and produced finer flour. He became the leading flour miller in the state.

Guenther trademarked twelve brands of flour by the end of the 1890s, and he also diversified into other businesses, such as an Ice Company and investing in brewing operations that began in San Antonio. He had intended to pass the entire businesses to his sons, but that plan took a detour when one of his sons built his own mill and marketed his flour under the brand of “Guenther Flour.” To avoid competing with his son, Guenther then, in 1898, renamed his mill “Pioneer Mills,” under which C.H. Guenther’s original enterprise still operates—the oldest continuous operating business in the state of Texas. That’s my story and I’m sticking to it.

The East Texas Historical Association provides this column as a public service. Scott Sosebee is a Professor of History at Stephen F. Austin State University and the Executive Director of the Association. He can be contacted at sosebeem@sfasu.edu or via www.easttexashistorical.org.