Long before the town had a famous son, it had a distinction of pure geometry. The state's point of geodesic equidistance — the mathematical middle of Ceará — falls inside this municipality, and Quixeramobim marks it with an obelisk about ten metres tall in Praça Dias Ferreira. Cearenses call the place the Coração do Ceará, the heart of the state, and they mean the phrase literally. Spreading out from that marker are 3,275 square kilometres of caatinga hiperxerófila, the driest register of Brazil's thorn-scrub biome, where the trees stand grey and leafless for most of the year and then turn green within days of a serious rain. Something like 85,800 people live here, which makes Quixeramobim the twelfth most populous municipality in Ceará. The Rio Ibu, also called the Quixeramobim, runs through the middle of it — seasonally.

Antônio's father, Vicente Mendes Maciel, ran a moderately successful business in the sertão, which in a landscape this poor counted as prosperity. His mother died in 1834, when he was four; his father remarried, drank, and the household turned hard. What saved the boy was his grandfather's schoolroom, where he worked through Latin, French, Portuguese, mathematics, geography and history and was remembered as a serious, hard-working pupil. When his father died in 1855 he took over the family business. He married in 1857. In 1861 his wife left him for another man, and the ordinary life he had assembled came apart. He withdrew to a farm, then to the road — wandering from 1865 to 1869, and again from 1871 onward, preaching, repairing chapels and cemetery walls, refusing payment. In 1893 that road ended at a place in the Bahian backlands called Canudos, where he founded the settlement he named Belo Monte. That is another story, and it did not end well.

The town assembled itself the way most sertão towns did: around a chapel and a water source. Captain Antônio Dias Ferreira began raising a chapel here in 1730, dedicating it to Santo Antônio de Pádua, and the settlement that gathered around it eventually took the saint's name along with the river's — the formal name is still Santo Antônio do Boqueirão de Quixeramobim. In 1789 it was elevated to a vila under the awkward, imperial-sounding label Nova Vila do Campo Maior. That name never took. In 1856 the place officially became simply Quixeramobim, a Tupi word carried over from the river, and the Portuguese bureaucratic title was quietly dropped. The Casa da Câmara e Cadeia — the old council house and jail, one building serving both functions, as was standard — still stands in the centre.

Everything here is organised around water that may or may not come. Rainfall concentrates into February, March and April; the rest of the year is dry, and the average temperature sits between 26 and 28 degrees Celsius. The record low is 13.7 °C, set on 2 August 1977, and the record high is 39.6 °C, on 19 October 1998 — a 26-degree spread that tells you how thin the air's memory is out here. Farming and ranching remain the primary occupations, and by 2012 Quixeramobim had the second-largest dairy output in the state, which is a genuinely surprising thing for a municipality of hyper-arid caatinga to achieve. Not all of the land is worked. The Paus Brancos district was designated a priority area for conservation and sustainable use when the Caatinga Ecological Corridor was created in 2006.

The municipality's register of notable places reads like a list of things the caatinga has refused to erase. Three archaeological sites — Pedra do Letreiro, the Lagoa do Fofô at Fazenda Jordão, and Fazenda Canhotinho — preserve traces of people who were working this landscape long before the chapel or the cattle. The Casa de Antônio Conselheiro and a memorial to him anchor the other end of the town's memory, and the fact that Quixeramobim keeps both the house and the memorial says something: the Republic treated Conselheiro as a fanatic and a threat, and his birthplace has decided otherwise. The town has also produced the composer Fausto Nilo and the footballer Iarley, born in 1974, who won the FIFA Club World Cup in 2006. A metal bridge, three old churches and a reservoir round out the inventory.