Hadijatou Mani was sold into slavery at the age of 12. She was beaten, raped and even imprisoned for bigamy after she married a man other than her “master”.

Astonishingly her story is not that rare in Niger, but now it has a happy ending. In an historic ruling that will resonate across West Africa, where slavery is still rife, Ms Mani won a landmark case yesterday against the Niger Government for failing to protect her.

“I am very happy with this decision,” Ms Mani, 24, told reporters outside an international court in neighbouring Nigeria. “Nobody deserves to be enslaved. We are all equal and deserve to be treated the same.”

The Court of Justice of the Economic Community of West African States (Ecowas) ordered Niger to pay Ms Mani 10 million CFA francs (£12,400) in compensation. The judgment was embarrassing for a government that said it had done all it could to eradicate slavery, but it offered hope for thousands of other men and women in the Sahel region.

The ruling sent a strong message to other governments that more needed to be done to set slaves free. Niger's neighbours, Mali and Mauritania, are also known to turn a blind eye to the practice. Chad and Sudan, which are not members of Ecowas, also use slaves.

The case against Niger was brought with the help of the British organisation Anti-Slavery International (ASI) as a test case to pressure African governments to end slavery.

Romana Cacchioli, the Africa expert of the ASI, said: “This will help free other women all over the region ... There is nothing more fundamental than the right to freedom. People in Niger now know that if a slave can take the State to court and win, then they too can confidently stand up for their human rights.”

She said that her group had managed to free at least 80 women slaves in Niger in the past five years.

A government lawyer said that Niger would respect the ruling.

However, analysts said that the country - one of the poorest on the continent - had showed little determination to enforce anti-slavery legislation adopted only five years ago.

The court ruling will be binding on all member states and will have consequences for people elsewhere. “This historic verdict sets a legal precedent that we can take to neighbouring states where slavery remains an issue. Niger now needs to look closely at its customary law courts to ensure that there is an end to the discrimination of women and to the acceptance of slavery,” Ms Cacchioli added.

Ms Mani was sold to a man called Souleymane Naroua when she was 12 for about £300. For the next ten years she was forced to carry out domestic and agricultural work. She was raped at the age of 13 and forced to bear the children of her “master”.

“I was beaten so many times I would run to my family ... then after a day or two, I would be brought back,” Ms Mani told local reporters in Hausa, the language of the Sahel region on the southern fringe of the Sahara. “At the time I didn't know what to do but since I learnt that slavery has been abolished I told myself I will no longer be a slave.”

In 2005 Ms Mani's “master” freed her and gave her a “liberation certificate”, but when she left him and tried to marry another man he claimed that they were already married. A local court found in her favour and she went ahead with the wedding.

The verdict was overturned on appeal, however, and she was sentenced to six months in prison for bigamy. After she was adopted by ASI she took her case to the court of the Ecowas regional grouping.

She accused the Niger Government of failing to protect her. Even though slavery has been a crime for five years, human rights groups in Niger estimate that at least 40,000 people are still being kept as slaves.

For generations the children of a slave automatically became the property of their parents' “master”. Ms Mani said that one of the reasons she turned to the international court was to secure the freedom of her two children and ensure that they did not have to suffer the same fate.

“I hope that everybody in slavery today can find their freedom,” she added.

She plans to use the compensation to build a house, raise animals and farm. “I will also be able to send my children to school so they can have the education I was never allowed as a slave,” she added.

Although the judgment will ease the suffering of tens of thousands of people in West Africa it has no bearing on the fate of many more in Sudan, where Arabs in the north of the country have kept African southerners as slaves for centuries.

Mauritania's Moors have also kept Africans in servitude, sowing the seeds for sporadic and violent rebellions. Despite international criticism both countries have consistently refused to take strong measures to eradicate slavery.

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