JUAREZ, Mexico (Border Report) – An invading French army in control of his capital, Mexican President Benito Juarez brought his fledging government to Villa Paso del Norte in August 1865.

As he dealt with the invasion and some Mexican troops supporting the invaders, landowners approached the president with a local issue they had been pushing for years. The Rio Grande had shifted southward due to torrential rains in the last decade. They wanted him to get the land back.

Juarez told his foreign minister Sebastian Lerdo de Tejada to begin negotiations in Washington, D.C. The claim was ignored by a U.S. government that had taken half of Mexico’s territory 17 years earlier during the Mexican-American War (1846-1848), according to historian Martin Gonzalez de la Vara.

The treaty designated the Rio Grande as the new eastern border between the two nations, but the river did not stay put.

Compounding the problem was the rapid development of lands to the north of El Paso del Norte, centered around Franklin settlement, later El Paso, Texas. “In the 1860s, (it) was a boomtown,” said U.S. Park Ranger J.R. Lujan, of the Chamizal National Memorial. “It was growing so rapidly that when, somehow, a tract of land ended up in the U.S. side close to present-day El Paso, it was developed fairly quickly. That was at the core of the conflict.”

Juarez left El Paso del Norte less than a year after his arrival. The city adopted his name, Ciudad Juarez, in 1888, ending the name ambiguity with its younger neighbor to the north. The name El Paso dates back to 1659 and the founding of a church by the Spaniards: Misión de Nuestra Señora de Guadalupe de los Mansos del Paso del Norte. El Paso refers to the pass between two mountain ranges in the area.

It would take nearly a century before President John F. Kennedy made improving relations with Mexico part of his Cold War strategy. That included returning the disputed lands of El Chamizal to Mexico. Diplomatic notes were exchanged and signed on Aug. 29, 1963.

The Chamizal Monument in Juarez, Chihuahua, Mexico, towers in the background as US President Lyndon B. Johnson and Mexican President Diaz Ordaz sign the historic Chamizal Treaty. (Getty Images)

Kennedy’s successor, Lyndon B. Johnson, and Mexican President Gustavo Diaz Ordaz completed the handoff of more than 600 acres of El Chamizal to Mexico in 1967 to the roar of crowds at a parade next to an international bridge.

In this May 10, 2011, file photo President Barack Obama speaks about immigration reform at the Chamizal National Memorial in El Paso, Texas. (AP Photo/LM Otero, File)

Another 193 acres in the northern part of Cordova Island, one of the disputed territories, remained north of the redrawn river, as per Article 2 of the treaty. The Chamizal National Memorial in El Paso, Texas, sits on 55 of those acres. It includes a cultural center, art galleries, a theater, and an amphitheater. The Bridge of the Americas, called the Bridge of the Island of Cordova in Juarez until the 1980s, also stands on land covered by the treaty.

The deal included taking care of the meandering river.

“Part of the solution involved city projects to cement the channel so the Rio Grande would stay in place as it ran through El Paso so we wouldn’t have this problem again,” Lujan said.

Since then, El Chamizal has been a symbol of friendship with Mexico to the Americans, and a source of pride to people in Mexico.

“We have visitors from Mexico City, Veracruz, Chiapas that, once we tell them the history of El Chamizal, they really feel pride, patriotism. They feel really happy because, from 1848 through 1967, almost 120 years, no land taken from Mexico due to the Guadalupe Hidalgo Treaty was given back. The (territories) of the Chamizal was the only land given back by the Americans to the Mexicans,” said Luis Ulises Castañeda Martinez, historian at the Museum of History and Archaeology at the Juarez Chamizal Park.

The border wall and mountains in Juarez, Mexico in the background as seen from the Chamizal National Memorial in El Paso, Texas. (Photo by PAUL RATJE/AFP via Getty Images)

From the Mexican perspective, the American expansionism of the 19th century that claimed half of Mexico morphed in the 1960s into a geopolitical chess game that required a strong ally south of the Rio Grande.

“We are talking about the 1960s, the Cold War between a capitalist block and communist block. Politically, the (Soviet Union) was in talks with Mexico, so there were concerns Mexico may align with the communist block,” Castaneda said. “America saw that as a sign of danger. […] The Chamizal was a good option to make stronger bonds between Mexico and the United States.”

JFK’s assassination in late 1963 did not change this political imperative. Johnson and Diaz Ordaz in late 1967 made good on their predecessors’ agreement, more so with the eyes of the world focusing on Mexico as it prepared to host the 1968 Olympic Games.

“It was a good moment to show friendship and binational unity,” Castañeda said.

Today, the Chamizal Park is the largest green space in Juarez. Thousands of families throw picnics, listen to music and grill meat there every weekend.

The Juarez Chamizal Park attracts thousands of families every weekend. (Border Report photo)

South of the park, a highway now occupies the Rio Grande’s old course. Sunken soccer fields mark the river’s deepest penetration more than 100 years ago.

Castañeda said the Mexican government’s original plan was to create a living monument, with museums, public schools and sports fields. In the end, it settled for a park and a branch of the National Museum of Archeology and History, known here just as the Chamizal Museum. An elementary school also briefly opened; it was eventually taken over by the local university as a college prep high school, he said.