The first name was Salobinha, the name of the fazenda. By 1958 it had enough people to become a district of the municipality of Goias - then, briefly that same year, of the newly created municipality of Diorama. In 1963 it was promoted to full municipal status. The new name came from the topography: small hills - montes claros - stood nearby, and the Rio Claro ran about fifteen kilometers from the town center. Nothing about the origin was heroic. A rancher donated land, settlers arrived, houses went up, administrative lines were drawn and redrawn. In seven years the place went from a single ranch to a municipality, which is about how fast things could happen on the Goias frontier in the late 1950s.

Montes Claros sits in the extreme west of Goias, where the state borders Mato Grosso across the Araguaia. The closest towns are Aragarcas, 117 kilometers west, and Jussara, 56 kilometers to the east - distances that mean what they would mean anywhere the roads are bad. Four rivers bathe the municipality: the Rio Claro, the Araguaia itself along the western edge, the Caiapo, and the Rio das Almas or Rio dos Bois. These are the western tributaries of the Araguaia basin, waterways that eventually reach the Amazon by way of the Tocantins confluence hundreds of kilometers downstream. In every direction except east the land opens into the Araguaia floodplain - flat country, sweeping horizons, enormous skies.

The economy runs on cattle. In 2006 there were 255,000 head of beef cattle in the municipality, plus 16,500 dairy cattle - a herd of more than a quarter million on 220,739 hectares of land, much of it natural pasture. Soybeans have come in strong; by 2006, 7,200 hectares were planted and the harvest reached 21,000 tons. This is the Cerrado frontier that Brazil has spent four decades converting from wild savanna into one of the world's largest commodity-agriculture regions. Other crops grow in smaller amounts: rice, beans, corn, bananas. The town has two banks, nine industrial units, 131 retail units. Most of the people work in public administration, commerce, or on farms.

The population has been shrinking. Since 1980 the municipality has lost almost 1,500 inhabitants. Between 1996 and 2007 the decline slowed but did not stop - down another 0.142 percent each year, the kind of slow leak that means the same families staying while their children move south to find work. In 2007 there were 4,856 people living in the town itself and 2,988 in the countryside, which by then had crossed a threshold: urban dwellers outnumbered rural ones for the first time. The population density remains tiny, just 2.71 people per square kilometer. There are 429 automobiles in the municipality, one hospital with 14 beds, 16 schools, 2,357 students. No institutions of higher learning. The literacy rate in 2000 was 84.5 percent.

The MHDI score of 0.750 placed Montes Claros 78th of 242 Goias municipalities - middle of the pack, better than the poorer northeast of the state, worse than the booming south. The infant mortality rate in 2000 was 18.31 per thousand live births, a decent number by Brazilian interior standards. What Montes Claros has going for it is proximity: to the Araguaia, one of the great South American rivers; to Mato Grosso, which has boomed on agribusiness; to the expanding soy frontier that brings money to landholders and equipment to towns. What it lacks is a reason for newcomers to move in. Enemias Lino de Oliveira built the town by giving his land away. Seventy years later, the descendants of those settlers tend the cattle, plant the soy, send their children to the coast, and wait to see what the next frontier cycle will bring.