Trinity County is in the East Texas Timberlands region. The center of the county lies at 31°07' north latitude and 95°05' west longitude. Groveton, the county seat of government, is near the center of the county and ninety air miles north of Houston. The county's name is from the Trinity River, which forms its southeastern boundary. Trinity County covers 692 square miles of rolling to hilly terrain that extends diagonally from the Trinity River northeast to the Neches River. The area is drained by these rivers and by a number of creeks that drain into them; near the southern tip of the county the Trinity has been dammed to form Livingston Reservoir, which provides water and recreation for the area. Altitudes in Trinity County range from 150 to 400 feet above sea level. Most parts of the area have reddish soils with loamy surfaces and clayey subsoils; in the western parts of the county, the soils are light colored with sandy surfaces and clayey subsoils. The county's climate is subtropical and humid, with warm summers and an annual average precipitation of forty-six inches. Temperatures range from an average low of 38° F in January to an average high of 94° F in July; the growing season lasts 260 days.
Before the advent of the lumber industry in the 1880s, the area was covered by forests of immense trees as large as fifty inches in diameter with first limbs sixty to eighty feet above the ground. Though these forests were destroyed, many areas are now reforested, and much of the county is dotted with pine and hardwood forests. Sweet gum, black willow, hawthorn, water locust, willow, laurel, sycamore, redbud, dogwood, magnolia, chinaberry, green ash, winged elm, red maple, bass wood, iron wood, hickory, winged sumac, oak, and short leaf and loblolly pine grow in abundance. Trinity County harbors a wide variety of wildlife species, including opossum, Eastern Mole, pocket gopher, coyote, red fox, striped skunk, river otter, mink, beaver, deer, and armadillo. The area is also home to numerous snake species, from the harmless coachwhip and common garter snakes to the poisonous copperhead, Western cottonmouth, and diamond back rattler. Birds found in the area include great blue heron, ibis, marsh hawk, whippoorwill, mourning dove, roadrunner, and pileated woodpecker. About 59 percent of the land in the county is controlled by timber interests or the national government: almost 200,000 acres of the county's land is owned by lumber and paper companies, while the Davy Crockett National Forest covers more than 73,000 acres. In 1982 about 36 percent of the county was in farms and ranches; 83 percent of the area's agricultural receipts was from livestock and livestock products, especially cattle, milk, and hogs. Coastal and Bermuda grasses with winter ground cover of oats and rye were raised as feed for cattle, and local farmers also grew sweet potatoes, peaches, and pecans.
Artifacts from the Paleo-Indian and Archaic cultures have been found in the area that is now Trinity County, suggesting that it has been occupied by humans for perhaps 10,000 years or more. When the first Europeans explored the region it was inhabited by various Caddoan and Atakapan Indians, but diseases, especially smallpox, ravaged these agrarian peoples by the time the first Anglo-American settlers arrived. Various other tribes, including the Alabama, Kickapoo, Tantabogue, and Coushatta, settled in the area in the nineteenth century. In 1827, when the area was part of the Mexican municipality of Nacogdoches, it was granted to Joseph Vehlein, a Mexico City merchant, by the Mexican government. Vehlein never fulfilled the terms of his contract to settle 200 families in the area, and Mexican authorities later made several other grants to would-be colonizers, including María Guadalupe de Castro and Pedro José de Caro. The Indian population controlled the land until after the Texas Revolution, however, and the area seems to have attracted few if any European settlers until the 1840s.
In 1837 the Congress of the Republic of Texas established Houston County, which included all of the area of present Trinity County. The first recorded permanent white settler was a Jesse James, who settled on Alabama Creek in 1844, near a large Indian settlement. In 1845 John Gallion moved into the settlement and purchased the Indians' livestock and improvements. Though the subsequent fate of the area's Indian population is unknown, they seem to have moved to the Indian Territory. The earliest white settlers in the area lived primarily by hunting, eating the meat of their prey and sending pelts to eastern markets for whatever cash they would bring. On February 11, 1850, the Texas legislature established Trinity County. Jesse James, Benjamin B. Ellis, Solomon Adams, James Marsh, Henry Ward, John Gallion, and M. Duke Hornsby were appointed "to ascertain the centre of the county, to select two sites within five miles of the center suitable for site of the County Seat, [and] to hold an election to determine which would receive the most votes." In 1854 Sumpter, a primitive village, was declared county seat, and a small courthouse and jail were built; that same year the county's first post office was established there. By the late 1850s Trinity County was a thriving frontier area that profited from the steamboat traffic on the Trinity River. Though most of the county's inhabitants supported themselves through hunting and subsistence agriculture, plantation agriculture was becoming increasingly important to the local economy. By 1857 a number of wealthy slaveholders, including C. C. Tallifero, George Reese, and C. O. Wagnon, had moved into the area and established large plantations on which cotton and corn were grown. A saw and grist mill was built at Indian Camp Springs in 1857, providing lumber for frame houses and other structures. By 1860 there were 4,392 people, including 791 enslaved people and a free Black, living in Trinity County. Farms covered 63,000 acres in the county, and almost 12,000 acres were classified as "improved"; that year 94,834 bushels of corn, 2,945 bales of cotton, and 210 pounds of tobacco were produced in Trinity County, along with other crops such as potatoes, sweet potatoes, and beans. Over 10,300 cattle were reported in the county, along with 1,465 sheep. Meanwhile Sumpter, the county seat, had grown to include three hotels, a grocery story, and a saloon. The Trinity Valley, a weekly newspaper, was being published there.
Though the population of the county was divided over the issue of secession in 1860, when the Civil War began the area strongly supported the Confederacy. Three companies of soldiers were raised in the county for the Southern cause, including one unit which became part of Hood's Texas Brigade. The number of slaves in the county grew significantly during the conflict, possibly due to southerners fleeing west with their slaves; according to county tax records, the county's slave population increased to 1,227 by 1864. The Trinity County area also became a haven for Confederate deserters and criminals during the war, and public order broke down. Some of the county's most prominent men organized a vigilante committee; J. F. Moore, the county sheriff, led its operations. Though the vigilantes resorted to summary justice and lynched a number of men, the county was still in turmoil when the war ended. In 1866 three companies of Illinois infantry were stationed in Sumpter as occupation troops for Reconstruction, but the county's society continued to be turbulent and disorganized in the years just after the Civil War. The county's white population harbored a "spirit of resentment" against the federal troops, and the Ku Klux Klan conducted night rides and other operations intended to intimidate the newly freed Blacks in the area. Meanwhile, local citizens were also harassed by outlaws such as John Wesley Hardin, who grew up in Trinity County. According to Flora Bowles, who has written an extensive history of the county, violence and murder were almost commonplace during this time. The county's economy was disrupted by the Civil War and its aftermath; the number of acres in farms in the county dropped from 62,324 in 1860 to only 19,274 by 1870. Corn production and the number of cattle fell off in the area during the 1860s, and cotton production declined significantly; in 1870, 2,205 bales were produced, 25 percent fewer than in 1860. While the number of Blacks living in the county rose sightly during the 1860s, the White population declined by 10 percent. A new town, Pennington, was established in the northwestern part of the county in 1866, but by 1870 the county's total population had declined to 4,140.
The county's social and political geography shifted after 1872, when the Great Northern Railroad extended its tracks into the small village of Trinity, located in the southwestern part of the county. Almost immediately people began to move out of Sumpter to Trinity and Pennington, sometimes taking their homes and other buildings with them. In May 1873, a few months after the Sumpter courthouse burned with most of the county records, the town of Trinity became the seat of government for the county. The next year, after another election, Pennington became the county seat; its courthouse burned in 1876. Meanwhile, in 1873, former slaves established the small town of Nigton in the northeastern part of the county. Agriculture in the area revived during the 1870s. By 1880 there were 421 farms, encompassing 159,000 acres, in the county, and 25,000 acres were classified as "improved." That year local farmers devoted 6,802 acres to cotton and produced 2,666 bales; another 9,184 acres were planted in corn, and 4,048 acres were planted in wheat. The county's population had also begun to grow again, and by 1880 there were 4,915 people (3,740 Whites and 1,162 Blacks) living in the area.
In the early 1880s, after the Sabine branch of the International-Great Northern Railroad was built through the county, the area's economy and way of life were fundamentally changed. Attracted by the area's spectacular old-growth forests, a number of lumber operations, including the Trinity Lumber Company (1881), the Thompson-Tucker Lumber Company, (1883), and the J. T. Cameron Lumber Company (1883), rapidly moved into the area and opened sawmills. A new town, Groveton, appeared around the Trinity Lumber Company's mill and grew so quickly that in 1882 the county's voters chose to make it the county seat. New towns subsequently appeared in the county around other mills, as the lumber companies built houses, churches, schools, and eventually electric plants and waterworks, to accommodate their workers. By the early twentieth century company towns such as Willard (1909 population: 1,200), Josserand (900), Saron (1,200), and Westville (1,000) were home to the thousands of workers who cut, hauled, and sawed the area's timber. Black workers lived in segregated housing and attended segregated schools, churches, and meeting halls. The lumber industry also attracted a large number of transient workers who lived in portable camps that moved around the forests; as soon as these crews cleared the trees from an area, their houses would be placed on railroad flatbeds and carried to the next logging site.
While Trinity County's lumber operations dominated the local economy and drained labor away from the agricultural sector, farming nevertheless expanded in the county during the late nineteenth century. By 1900 there were 1,271 farms, encompassing 323,000 acres, in the area. Production of corn and cotton, the county's most important crops, increased steadily during this period and particularly during the 1890s; by 1900, 15,448 acres in the area were planted in corn, while 13,704 acres were devoted to cotton. The area's ranching industry also grew, and by 1900 over 20,000 cattle and 5,000 goats were reported in the county. Largely because of the lumber industry, but also because of this farm expansion, Trinity County's population grew to 7,648 by 1890 and to 10,976 by 1900. Lumbering in the county intensified during the early 1900s. Production was prodigious; one mill alone, owned by Thompson-Tucker Lumber, turned out 100,000 boardfeet of lumber daily in 1909. By that time, however, the county's old forests were almost played out. The town of Josserand died in 1909, when its mill closed that year, and Willard folded up in 1911 for the same reason; Saron died in 1919 and Westville in 1921. By 1928 only the lumber operations in Groveton and Trinity were still operating, and the companies that owned these mills were reaching into Tyler and Houston counties for their logs. Only ugly stumps and brush covered much of Trinity County, and the once-thriving sites of Willard, Josserand, Saron, and Westville were only "waste places covered with brambles." The Groveton mill closed at midnight on December 31, 1930, blowing its steam whistle for two hours to signal the end of an era in the county's history. Farming had declined in the county during the lumber boom of the early 1900s, but as the mill industry began to die, many of its former workers turned to farming. They were encouraged by Helen Kerr Thompson, the wife of the president of the defunct Thompson-Tucker mill. In her attempt to revive agriculture in the area, Mrs. Thompson built chickenhouses and filled them with purebred leghorn hens, stocked a ranch with registered Hereford cattle, and began a diversified farming program that focused on growing cotton, sugar cane, and various grains. She took on tenant farmers to work some of her lands. About 100,000 acres of the county were in farms in 1925, but by 1930 farmland in the area had expanded to encompass more than 143,000 acres. During that same period the number of farms in the county grew from 1,330 to 1,569. By 1930 almost 25,000 acres in the county were planted in cotton, more than twice the figure for 1920. Many of the new farmers were tenants; the number of farms in the area operated by tenants grew from 465 in 1920 to 726 by 1930. The expansion of agriculture in the area helps to explain why the county's population did not drop after the mills closed. There were 12,768 people living in the area in 1910, 13,623 in 1920, and 13,637 in 1930.
Despite the agricultural expansion, the closing of the mills and the onset of the Great Depression had severely undermined the local economy. By the early 1930s a number of people had already moved out of Groveton, the county seat, and the town had lost some of its finest buildings to fires. The main railroads in the area stopped running, and the county had almost no paved roads aside from State Highway 94, which was completed between Groveton and Trinity in 1929. New Deal projects sponsored by the federal government did much to revive the area and to prepare it for the future, however. The Civilian Conservation Corps established camps at Trinity, Apple Springs, and Groveton and hired a number of young men for reforestation work, road construction, and erosion prevention measures. Sewing rooms were opened in the county to employ local women, and the Work Projects Administration built a new county jail and constructed high schools for Apple Springs, Pennington, Saglen, Centerville, and Groveton. Meanwhile, the Woodlake area became the site of an experimental federal commune under the Texas Rural Community Project. About 100 houses were built on three-acre tracts and filled with families selected from the relief rolls. The Woodlake community also became the base for a National Youth Administration camp, where as many as 150 young people at a time were trained in industrial crafts. The population of the area increased slightly during the 1930s to reach 13,705 by 1940.
Trinity County's population declined significantly during the 1940s and 1950s as farms mechanized and consolidated; by 1950 there were only 975 farms in the county, and young people left to look for new opportunities elsewhere. Thanks to reforestation efforts, however, the lumber industry eventually revived, and by the 1960s there were two sawmills operating in the county. By the 1980s the area's timber production exceeded the yields of the timber boom of the early 1900s, and timber sales provided most of the county's revenue. Natural gas and oil were discovered in the county in 1946, but production levels remained low into the 1990s. About 20,000 barrels of crude were produced in the area in 1960, under 5,000 barrels in 1974, about 1,800 barrels in 1982, and about 64,000 barrels in 1990. In the 1960s the Trinity River was dammed to form Lake Livingston, which immersed part of the county and now provides recreation for the area's inhabitants and tourists. The population of the county steadily increased after the 1960s, reaching 7,628 in 1970, 9,450 in 1980, and 11,445 by 1990.
The voters of Trinity County supported the Democratic candidates in every election from 1852 through 1968. The area’s sympathies began to change in 1972, however, when Republican Richard Nixon carried the county, as Ronald Reagan did in 1984. Though Democratic presidential candidates won majorities in the county in 1976, 1980, and 1988, the elections of 1972 and 1984 marked the beginnings of a shift away from the area’s traditional leanings. Democrat Bill Clinton won a plurality in the county in 1992 and won outright in 1996, but Republican George W. Bush won solid majorities in the 2000 and 2004 elections.
In 2014 the census counted 14,224 people living in Trinity County. About 78.9 percent were Anglo, 9.6 percent were African American, and 9.2 percent were Hispanic. More than 73 percent of residents older age twenty-five had four years of high school, and more than 9 percent had college degrees. In the early twenty-first century forestry, cattle, and tourism were important elements of the area’s economy. In 2002 the county had 555 farms and ranches covering 104,724 acres, 41 percent of which were devoted to crops, 39 percent to pasture, and 18 percent to woodlands. In that year local farmers and ranchers earned $8,953,000, with crop sales accounting for $8,605,000 of that total. Beef cattle and horses were among the chief agricultural products. More than 19,271,000 cubic feet of pinewood and 3,680,000 cubic feet of hardwood were harvested in the county in 2003. Groveton (population, 985) is the county’s seat of government and Trinity (2,545) its largest town. Other communities include Apple Springs (350), Sebastapol (300), Woodlake (180), Pennington (67), and Centralia (190). The town of Trinity holds a spring festival each May and a community fair in September.