Somber Angelina Jolie Attends Sentencing of Congolese Warlord at The Hague

Angelina Jolie isn't one to miss a history-making moment.

The actress, director and UNHCR Goodwill Ambassador, 36, arrived in Amsterdam on Tuesday with daughters Zahara, 7, and Shiloh, 5, for a visit that had nothing to do with a splashy film premiere.

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Instead, Jolie sat in the public gallery Wednesday morning for the first-ever verdict at the International Criminal Court in The Hague, 10 years after it opened.

After 200 days in court, vicious Congolese warlord Thomas Lubanga was finally convicted of kidnapping and recruiting young children -- forcing them to become child soldiers to fight for Congolese rebel sources.

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"This is their day," Jolie said in a statement. "Where these children will feel there is no impunity for what happened to them, for what they suffered."

"Angelina was very low key," an onlooker at The Hague tells Us Weekly. "She came in almost unnoticed to watch the verdict and left right afterwards."

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The case of 51-year-old Lubanga could set a precedent for Uganda guerilla warlord Joseph Kony, currently the subject of a giant, celeb-supported viral campaign aimed at bringing him to justice.

Over the weekend, Jolie was by Brad Pitt's side in New Orleans for his Make It Right Foundation's huge, star-studded bash.

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