Prosecutors in the trial of accused militia leader Thomas Lubanga turned to a historian this week to explain the origins of the ethnic conflicts that have plagued the Ituri region of the Democratic Republic of the Congo (DRC).

Author and historian Gerard Prunier provided the court with an overview of the ethnic tensions that erupted into violent clashes across the Ituri region between 1999 and 2005, involving people of the Lendu and Hema tribes.

In the conflicts, Lubanga’s Union of Congolese Patriots (UPC), which represented the minority Hema in the region, fought with Lendu militias.

The long-simmering animosities were rooted in the colonial era under Belgian rule, which controlled the entire Congo until the country’s independence in the early 1960s, Prunier explained. Very little political structure was left once the Belgians relinquished power, he said.

“People focused on the lowest common denominator. They focused on what they knew,” Prunier told the court. “And that was their tribal allegiances.”

He told the court that Belgian rule granted the Hema people greater political power than the Lendu people, despite the fact that the Lendu people were greater in number.

Land disputes led to what Prunier called “ethnic radicalization,” and “a cycle of vengeance and counter vengeance.”

The military power of the Hema people was also strengthened by the assistance of the Ugandan military, Prunier said, which helped the Hema appropriate Lendu lands in the late 1990s.

Defense lawyer Jean-Marie Biju-Duval questioned Prunier on the alleged alliance between Ugandan forces and the UPC, citing hostile incidents between the two parties in 2003.

Prunier said that alliances between parties, countries, and ethnicities tend to switch easily and swiftly in Africa because the leadership is not typically driven by ideological interests. Rather, alliances are formed for practical reasons. When those reasons evaporate, so do the allegiances, Prunier said.

“So, your theory is the allegiance between Thomas Lubanga and Uganda evaporated with his arrest in Kampala in 2003?” Biju-Duval asked.

“Yes,” replied Prunier, “with the possibility that things could work out again for them in the future.”

Biju-Duval also questioned the possibility of an allegiance between Uganda and the UPC based on conflicting information that came from the United Nations.

Prunier said the UN’s mission to the Congo knew about Uganda’s involvement in the Ituri region, but did nothing about it.

“The international community shows a tolerance for what happens in Kampala and Kigali, perhaps partially because of what happened in the Rwandan genocide,” Prunier told the court. “The international community has a significant influence on the UN.”

In 2006, a UN report on the exploitation of natural resources in the eastern DRC was released that criticized Uganda for its role in the Congolese conflicts.

Prunier accounted for the UN’s lack of action by explaining that the report was written by an independent group of experts. While the UN may know about the problem, yet do nothing about it, that dilemma “gets to the heart of the problem with the UN.”

Earlier in the week, two other witnesses provided intimate glimpses into UPC politics and leadership.

When questioned about his written statements, a judge from Ituri described justice in the region as being based on whichever rebel group held power at any given time.

While the UPC held power, he said, it was impossible to investigate cases relating to ethnic conflict-even if the guilty parties were well known.

A minor leader in the UPC testified about the UPC’s organizational structure. Although his face and voice were digitally distorted during the public sessions to protect his identity, most of his testimony was given in closed session.