Petroleum County is a county located in the U.S. state of Montana.
 As of the 2010 census, the population was 494, making it the least populous county in Montana and the seventh-least populous in the United States.
 Its county seat is Winnett.
 The Montana Legislature approved the formation of the county by separating it from Fergus County; Petroleum County was thus created on February 25, 1925, as the last of Montana's 56 counties.
Sanders County is a county located in the U.S. state of Montana.
 As of the 2010 census, the population was 11,413.
 Its county seat is Thompson Falls.
 The county was founded in 1905.
The Johnston Library is a historic library located at 210 W. 10th St. in Baxter Springs, Kansas.
 The building was constructed in 1872 to serve as a courthouse during Baxter Springs' unsuccessful attempt to become the Cherokee County seat.
 Though Baxter Springs had lost an election to choose the county seat in 1869 to Columbus, supporters of both cities had attempted to fraudulently swing the election in their favor, and Baxter Springs hoped it could still become county seat in the future.
 The building initially served as the county jail and sheriff's office until Columbus completed its jail in 1880.
 After this, Baxter Springs ultimately gave up its attempts to become the county seat, and the building became its city hall.
 In 1905, resident Niles P. Johnston bequeathed $5,000 to the city to start a library, and the city hall building was chosen to house it.
The Former Audubon County Courthouse, also known as the Audubon County Historical Society Museum, is a historic building located in Exira, Iowa, United States.
 Court proceedings were first held in a schoolhouse in Hamlin’s Grove after Audubon County was established in 1851.
 The county seat was relocated to Exira ten years later, and a disagreement erupted over where the county seat should be located.
 The county board of supervisors made an appropriation for a new courthouse in 1871, but its construction was delayed due to the disagreement.
 Exira eventually won and officials constructed the courthouse for about $2,200.
 The Exira Hall Company was established to build the two-story, frame structure.
 County offices were located on the first floor and the courtroom was located on the second floor.
 The county seat was moved to Audubon in 1879.
Confederate Gulch is a steeply incised valley on the west facing slopes of the Big Belt Mountains in the U.S. state of Montana.
 Its small stream drains westward into Canyon Ferry Lake, on the upper Missouri River Valley near present-day Townsend, Montana.
 In 1864 Confederate soldiers on parole from the American Civil War made a minor gold discovery in the gulch, but in 1865 the discovery of the sensationally rich Montana Bar—one of the richest placer strikes per acre ever made—led to other rich gold strikes up and down the gulch, and touched off a frantic boom period of placer gold mining that extended through 1869.
 From 1866 to 1869 the gulch equaled or outstripped all other Montana Territory mining camps in gold production, producing an estimated $19 to $30 million in gold—late 1860s money.
 For a time, the gulch became the largest community in Montana—in 1866 Montana had a total population of 28,000, and of these, about 10,000 (35%) were working in Confederate Gulch.
 The main community was Diamond City , and while gold production was at its height, Diamond City roared along both night and day.
 During its heyday, Diamond City was the county seat of Montana's Meagher County, although today the area has become part of Broadwater County.
 In their frantic efforts to get at more gold, the miners built ditches and flumes that extended for miles, and employed high pressure hydraulic mining methods which washed down whole hillsides and ate up the gulch floor.
 The hydraulic mining process stripped the gulch and left huge spoil banks—hydraulic mining even consumed the site of Diamond City, which had to be moved to a new location.
 Then the gold ran out, the boom was over and the population simply picked up and left.
 In 1870 there were only 255 people left and a year later only about 60.
 Today hardly a trace remains of Diamond City or the other gulch communities.
 The gulch is quiet and empty, with only an occasional summer prospector, or a rare traveler using the unimproved road that still winds up the gulch from the Missouri Valley and crosses the top of the Big Belts on its way down to the Smith River Valley.
 Diamond City, Confederate Gulch and the Montana Bar were spectacular examples of the flash-in-the pan Montana placer gold mining camps, but what a flash.
Weeksville is a census-designated place (CDP) in Sanders County, Montana.
 The population was 83 at the 2010 census.
The Old Allamakee County Courthouse, located on 2nd Street in Lansing, is a short-lived former county courthouse of Allamakee County, Iowa.
 The courthouse was completed in 1861 amid a fight between Lansing and Waukon over which community deserved to be the county seat.
 Lansing had lost a vote on the county seat to Waukon in 1859, but they won another vote in 1861 after teaming up with the community of Columbus.
 Waukon built its own courthouse in the meantime, but it failed to win back the county seat in yet another vote in 1864.
 The county sheriff, a Waukon resident, attempted to seize the county's records from the Lansing courthouse in 1866; however, a posse from Lansing stopped him before he could return to Waukon.
 The Iowa Supreme Court decided the county seat battle in favor of Waukon the following year; it has remained there since.
Jasper County Community Unit School District 1 is a unified school district based in Jasper County's county seat of Newton, Illinois; it is the only school district in the county and is, consequently, the main educational body in all of Jasper County, although it serves portions of Effingham County and Cumberland County as well.
 This school district is composed of six schools in total; four elementary schools, one junior high school, and one high school.
 There is also a prekindergarten program run at the high school of the district should parents wish to enroll their children early.
 Willow Hill Elementary School, which is located in the village of its namesake, serves only kindergarteners; its proximity to the county seat and central position in the county allows its students to dawn from all parts of the county and still have easy access to the elementary school they will attend.
 The principal of Willow Hill is Dave Parker.
 Grove Elementary School is located in Island Grove, Illinois, the highest point of elevation in the county.
 Grove Elementary School educates students from kindergarten to grade six, and it runs a prekindergarten program as well.
 Craig Carr is the principal of this school.
 Ste. Marie Elementary School is located in the southern Jasper County village of Ste. Marie, and serves students in grades one through six.
 The principal of Ste. Marie is David Parker, the principal of Willow Hill Elementary School.
 Newton Elementary School is located in the county seat of Newton, and serves most of west Jasper County's first through sixth graders under principal Travis Wyatt.
 The latter three elementary schools feed into Jasper County Junior High School and are taught in the facility during seventh and eighth grade while being supervised by Newton Elementary School principal Travis Wyatt before graduating into Newton Community High School.
 Students in grades nine through twelve spend their last leg of precollegiate education at this school; their principal is Ruth Kerner.
 The district superintendent is Ron Alburtus, and the district's mascot is the eagle.
Choteau is a city in and the county seat of Teton County, Montana, United States.
 It lies along U.S. Routes 89 and 287 (the latter terminating at the former in this city) about 20 mi east of the Rocky Mountains, near Flathead National Forest, the Rocky Mountain Division of Lewis and Clark National Forest, and Glacier National Park.
 The population was 1,684 at the 2010 census.
 The Montana town is named for French fur-trapper and explorer Pierre Chouteau, Jr., who is also the namesake of Chouteau County, Montana (county seat: Fort Benton).
The Gardnerville Branch Jail is a historic jail located at 1440 Courthouse St. in Gardnerville, Nevada.
 The jail was built in 1910 and served as Douglas County's only jail from 1910 to 1915.
 Prior to 1910, the only county jail was in Genoa, the county seat; however, since Gardnerville was several miles from Genoa, it resorted to housing prisoners in the local judge's granary.
 As the granary was considered unfit for holding prisoners, the community petitioned the county to construct a new jail.
 However, local leaders in Minden, who wanted to move the county seat to their town, protested the move, as they suspected that Gardnerville was attempting to claim the county seat itself.
 Nonetheless, the county approved the construction of the new jail.
 The jail housed its first prisoners before construction even finished, as the Genoa jail burned down; one prisoner was briefly chained to a post until the new jail could accommodate him.
 Once completed, the jail served the county until 1915, when Minden became the county seat and opened its own county jail.

Question: What is the county seat for the county in which Weeksville, Montana is located? 
Answer: Thompson Falls