Ethio­pian Prime Minister Meles Zenawi died late Monday while being treated abroad for an undisclosed illness. He was part of a coalition of rebel groups that overthrew former Ethiopian dictator Mengistu Haile Mariam in 1991, and he became Ethiopia’s president soon after. Meles became prime minister in 1995 and had been in power since.

Meles leaves behind a mixed legacy: His government was at times a strategic ally of the United States in the region, but his autocratic style garnered scorn from human rights groups. Here are five things to know about the late ruler:

View Photo Gallery: Meles Zenawi, Ethiopia’s long-time ruler who held tight control over this East African country but was a major U.S counter-terrorism ally, died of an undisclosed illness after not being seen in public for weeks.

He was a pseudo-communist doctor-in-training:

Meles dropped out of medical school to join the revolution and, after becoming president, distanced himself from his self-described “intellectual communist views,” leading the international community to begin describing him as a “mellowed Marxist.”

“The ... provisional government unwaveringly believes that it can solve all the present problems together with the broad masses of Ethiopia. However, we can do this only if all the people come out in unison to implement our planned undertakings. Above all, let us contribute our share in our respective areas for the prevalence of absolute and complete calm, in towns and rural areas,” Meles said in a 1991 address to the nation.

He oversaw significant economic growth:

Ethiopia’s GDP grew from 3.8 percent in the ’90s to 10 percent in 2010, and officials expect 11 percent growth this year, Reuters reported, thanks to rising agricultural output.

Much of the boom can be attributed to foreign investment and the leasing of land to China and India, but the country also embarked on new energy and infrastructure projects under his rule.

Meles was a key ally of the U.S. in the Horn of Africa

His government allowed the United States to deploy Reaper drones into Somalia from a base in southern Ethi­o­pia, according to reports by The Washington Post’s Craig Whitlock. Between 2006 and 2009, he also sent Ethio­pian troops into Somalia to fight Islamist militants.

... But he has an ugly human rights record

One Ethio­pian critic, Assefa Seifu, called Meles “a devil incarnate,” the BBC reported.

Human rights groups condemned him for sweeping crackdowns on dissent, including the deaths of 193 political protesters in street demonstrations during the 2005 election and a 2009 antiterrorism law that some rights organizations believe could be applied to any and all opposition groups.

More than 10 journalists have been charged under the law, according to the Committee to Protect Journalists, and two Swedish journalists were jailed for 11 years on charges of entering the country illegally and aiding a rebel group, according to Reuters.

He leaves behind somewhat of a power vacuum

Deputy Prime Minister Hailemariam Desalegn will take over as acting prime minister, per Ethio­pian law.

“I would like to stress, nothing in Ethiopia will change,” said information minister Simon Bereket. “The government will continue. Our policies and institutions will continue. Nothing will change in Ethiopia.”

There is a chance, however, that Meles’s passing could lead to instability in the region. Several writers who follow the country have speculated there’s a chance Ethiopia’s political parties could struggle for power, or that Eritrea, which seceded in 1991, could seize the moment to weaken Ethi­o­pia.

“I think the threat about the instability that many are referring to is actually connected to the idea that he has been in charge of the country for so long and that he’s had an opportunity to make himself, or his personality, stand out to many of the goings on in the country,” Andrew Asamoah, a senior Horn of Africa researcher at the South Africa-based Institute of Security Studies, told Voice of America. “So [there’s] the fear that his sudden exit has the capacity of dislocating the arrangements of the quality of the country.”

This post has been updated.

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