PARIS — The International Criminal Court in The Hague sentenced a Congolese warlord to 14 years in prison on Tuesday for using child soldiers in his rebel army in 2002 and 2003. The sentence was the first imposed by the court in its history.

Thomas Lubanga, a psychologist turned militia leader, was found guilty in March of “widespread” use of girls and boys under the age of 15, who were often abducted by his group, trained and then used to terrorize and kill villagers in the Ituri region of the Democratic Republic of Congo.

The presiding judge, Adrian Fulford, said that the sentence reflected “undoubtedly very serious crimes” that violated the protections that must be afforded to children. But the sentence was far short of the 30 years the prosecution had sought.

Mr. Lubanga, 51, who once led the Union of Congolese Patriots and asked every family in his region to contribute a cow, money or a child to his militia, will receive credit for the six years he has already spent in custody in The Hague. If he ends up in a European prison, his sentence could be further reduced if he is released on good behavior after serving two-thirds of his sentence, a common practice on the Continent.