Former Mexican President Luis Echeverria’s 100. died at the age of

Mr. Echeverria served as president from 1970 to 1976 at the height of Mexico’s single-party rule by the Institutional Revolutionary Party, which ruled almost without challenge from 1929 to 2000.

In 2006, a few days before the opening of the Summer Olympics, Mr. Echeverria was indicted on genocide charges in connection with the 1968 Tlatelolco massacre of students in Mexico City. He was under house arrest for three years until a judge ordered his release in 2009, citing lack of evidence.

Mr. Echeveria gained international fame as a leading voice of developing countries seeking an alternative to the Cold War rivalry between Washington and Moscow.

Mexico at the time was seen as a beacon of political stability in a region plagued by social unrest, frequent military coups and guerrilla movements. He pursued leftist policies at home and abroad, but his term as president was marked by repression of Marxist guerrillas, students and opposition groups.

“Echevería presided over one of the darkest times in Mexico’s recent history,” said Soledad Loeza, a political scientist at El Colegio de México, who was 20 when Trump was elected. Echeveria took over.

Hundreds went missing during his presidency.

During his tenure, the turmoil of the Cold War in Mexico intensified. Eugenio Garza Sada, a prominent industrialist in the northern city of Monterrey, was assassinated in 1973 in an attempted kidnapping by a communist guerrilla group.

As president, Mr. Echeveria exercised almost absolute power. He controlled the Congress and the Supreme Court, while the ruling party faced only symbolic political opposition. Mr Echeverria ruthlessly repressed opponents, while popularizing left-wing rhetoric not heard since the 1930s, when President Lazaro Cárdenas nationalized the oil industry, Ms Loeza said.

Mr. Echeveria implemented protectionist policies that resulted in rapid industrialization, which spurred economic growth. But high public spending and rising public debt led to a devastating currency devaluation after more than two decades of economic stagnation.

Mr. Echeveria was known for his oratory, long speeches and rhetorical skills. Mexican historian Daniele Cosio Villegas described Mr. Echevería as a brash leader who skillfully used words and lengthy speeches as a governing tool. “He was a preacher,” wrote Mr. Cosio Villegas in a 1975 book.

Many analysts say that Mexico’s current president, Mr. López Obrador, shares a similar rhetoric and is also a strong defender of an active state role in the economy. Mr. Echeverria often went to the remote countryside, a practice adopted by Mr. López Obrador.

“Both leftists are populists,” said Roger Bartra, a historian and sociologist. “López Obrador sees the years of Echevería as a golden age of government spending and state control.”

Mr. López Obrador began his political career at the end of Mr. López Obrador. Echeveria’s government, and several politicians who served with Mr. Echeverria has also served in the López Obrador administration.

Mr. Echeveria was born in Mexico City in 1922. A lawyer by training, he cut his political teeth when he joined the PRI at the age of 24. Tall and slender, he rose through the ranks of the party in several administrations, earning the reputation of being a disciplined and efficient bureaucrat.

In 1964, then-President Gustavo Diaz Ordaz named him Minister of the Interior, an important post that often led to the presidency. As minister, he oversaw national security when soldiers and government-aligned paramilitary agents opened fire on a student rally in Tlatelolco Square in 1968.

Official records show that 44 people were killed, according to an investigation by the US non-profit National Security Archives. Student organizations and news reports at the time estimated 150 to 300 deaths. Mr Echeveria has denied ordering the killings.

The repression continued under the chairmanship of Mr. Echeveria. He won the 1970 election after being chosen by Mr. Diaz Ordaz as the candidate of the ruling party.

According to Mexico’s National Human Rights Commission, 532 people went missing at the hands of state forces in the 1970s. The commission documented 275 extrajudicial executions. Most of them were leftist students, activists and farmers who organized in secret groups in the chaotic state of Guerrero in southern Mexico.

According to official records, government-controlled agents killed at least 12 people and injured several others in the 1971 demonstration. The event was featured in Mexican director Alfonso Cuarón’s 2018 Oscar-winning film “Roma”.

Mr Echeveria refused to order the attack. In 2005, a judge dropped the genocide charges in relation to the 1971 attack, citing a lack of evidence.

Despite Mr. Echeveria’s repressive policies, many intellectuals, including prominent writer Carlos Fuentes, were pleased with his anti-American rhetoric and personal closeness with leftist Latin American leaders such as Salvador Allende of Chile and Fidel Castro of Cuba.

“Mexican intellectuals supported him greatly. He believed that the election in the 1970s was between the PRI and the right-wing military dictatorship that ravaged the continent at the time,” said Ms. Loeza.

He was also known for his attacks on the independent media. In July 1976, just five months before leaving office, Mr. Echeverria planned to remove Julio Scherrer, a government critic and managing editor of Excelsior, one of Mexico’s leading newspapers at the time.

The move would become one of Mr. Echeverria’s enduring contributions to Mexico: Mr. Scherer founded the weekly Proceso, one of the most influential news outlets in the country.

write to Juan Montes juan.montes@wsj.com