Ntaganda has been charged with 18 counts of war crimes and and crimes against humanity for his involvement in alleged atrocities carried out in Congo's northeastern Ituri province in late 2002 and early 2003.

Charges include recruiting and using child soldiers as well as murder, rape and sexual slavery.

These were allegedly committed while Ntaganda was deputy chief of staff of the military wing of the Union of Congolese Patriots.

In 2012, the rebel group's leader, Thomas Lubanga, was found guilty by the ICC of committing war crimes and sentenced to 14 years imprisonment. 

As Ntaganda's troops advanced, "men women and children were shot or hacked to death," said prosecution lawyer Nicole Samson during closing arguments for the trial in August 2018, according to a trial report published by the International Justice Monitor.

"The crimes weren't isolated incidents … they were large-scale and systematic, resulting from meticulous training by Ntaganda," Samson was quoted as saying at the end of the three-year trial held in the Dutch city of The Hague, the seat of the ICC.

In the Congolese village of Kilo, rape was so widespread that antibiotics were distributed to treat rebels suffering from sexually transmitted infections, Samson said.

Savage ethnic attacks

ICC prosecutors said the attacks primarily targeted people according to their ethnic origin, such as those belonging to the Lendu, Bira and Nande groups.

Speaking ahead of the verdict, a Lendu community spokesperson in DR Congo said the Lendu people were "expecting a great deal" from the ICC.

Read more: ICC orders damages for victims of Congolese warlord 

"We would like the ICC to ensure that the victims of these crimes have their rights restored and are compensated for the crimes committed by Bosco Ntaganda," Jean-Marie Ndjaza, vice president of the Lendu community, told DW.

"We have no doubt that he will be convicted and we have confidence in the ICC," he said.

Ntaganda  has denied all charges.

Long road to verdict

Luc Malembe, a resident of Bunia in Ituri province, said regardless of whether the ICC declares Ntaganda guilty or innocent, people in the region have been waiting "too long" for justice.

The ICC issued a warrant for Ntaganda's arrest in 2006 but he wasn't detained until 2013, with the trial beginning in 2015.

In neighboring North Kivu province, Ntaganda's verdict will also be closely watched on Monday.

This is because after leaving the Union of Congolese Patriots and a stint as an army general, Ntaganda founded a new rebel group, the M23, in 2012.

Led by Ntangda, the M23 is similarly accused of grave abuses such as summary executions, rapes, and forced recruitment of children — this time in North Kivu province. 

The ICC is not trying Ntaganda for these later crimes.

"We are happy that the ICC will deliver its verdict on Monday," said Mireille Kavira, a resident of Rutchuru in North Kivu.

"We from North Kivu hope that the same court will look into the crimes that Ntaganda committed in North Kivu and if such a trial takes place, then justice will be served," she told DW.

Before being defeated by the UN and Congolese forces in 2013, the M23 rebel group controlled huge swaths of the country's mining heartland in the east. It even managed to seize control of Goma, the North Kivu provincial capital.

Tens of thousands of people were forced to flee the conflict between Congolese forces and M23 rebels.

John Kanyunyu in Kinshasa contributed to this report.