History to the cities of the Triple Border in a Nutshell:

Modern history of the Three-Country Area starts in the early 1800s with Argentine businessmen pioneering the setting up of yerba mate (Illex paraguayensis or Ilex paraguariensis) production camps (of a sort) and lumber exploitation. Four words and as many concepts have been shared by the three countries converging here: exploitation and slavery, yerba mate and lumber. In connection with these I would like to add another three: mensú, obraje and obrajero. They send us back to the former four. The Obraje was a huge tract of land measured into the hundreds of square kilometers that were normaly given by the govenments so that groups could exploit lumber, yerba mate, furs, live animals. All that done thanks to special methods of exploiting people. Obrajeros were obraje owners a few of them known to these days thanks to their infamous fame. (Obrajes were not a local invention. There were obrajes all over Latin American mainly in the textile fields*)

Just like what was seen in the rubber baron period in the Amazon, obraje owners used similar methodos to make people work for no pay. One of the trick was to forward money for newly hired workers so that they could acquire the food necessary for a certain period, tools (ax,knives, guns, bullets), tobacco, salt, sugar, kerosene or fat. Whatever the sum to be paid, workers would work for the rest of their lives and never be able to finish payment. Obraje owners had strong men to keep an eye on would-be fugitives and they had no problem at all to kill those who tried. Like the Amazon where the infamous Peruvian Casa Arana's rubber baron killed thousands of Indians, obraje lords used same methods. At a place by the Itaipu Dam there was one such terrible place. Payday, in many places, was normally the worker's last day.

Foz do Iguaçu (Brazil), Puerto Iguazu (Argenina),Hernandarias and Presidente Franco (Paraguay) sprang from different 'obrajes'. Hernadarias was the oldest. It was the seat of Industrial Paraguaya S.A.a jungle holding covering 35% of the land of Estaren Paraguay. Foz do Iguaçu, officially founded as the Iguassu Military Colony in 1889, belonged till the military arrived to British and Argentine concerns the main one being the Fazenda Britania. When the Brazilian Imperial Forces arrived to what is being called today the Triple Border, over 300 people of different nationalities lived on the no man's land. After foundation, the land around the colony was claimed by the military forces and served later as the land to be given over to the Municipality of Villa Iguassu and later Foz do Iguassu (Foz do Iguassu).

On the Paraguayan side, snall Puerto Pesident Franco, today a city, was the home of a 'obraje'. The one that lasted longer than any other obraje on the Paraná River Coast. Being a Tri-National Obraje land, the Tri-Junction area was a specialized slave land where people have behaved like mensús even to this day. Mensu worker comes from "mensual" (monthly) in relation to payment. Workers were promissed monthly payments for their jungle lumber work and later yerba mate collecting, preparing, drying, carrying, packaging work.

The regional Paris of the Paraná River in those days was Posadas. It was there that mensus were hired. Where menus spent their money paying exorbitant prices for drink and sex and as soon as their money finished were returned to the obraje or sent to a new one under a new contract. Quiroga says that Posadas was the Jeruslaem and the Golgotha of their lives.

* Suggested reading on Obrajes
The Cambridge Economic History of Latin America - the Colonial Era and the Short Nineteenth Century. You might want to see my Chronology of the Triple Border.