Slavery in Niger involves a number of different practices which have been practiced in the Sahel region for many centuries and which persist to this day. The Bornu Empire in the eastern part of Niger was an active part of the trans-Saharan slave trade for hundreds of years. Other ethnic groups in the country similarly had a history of slavery, although this varied and in some places slavery was largely limited to the political and economic elite. When the French took control of the area they largely ignored the problem and only actively banned the trade in slaves but not the practices of slavery. Following independence, many of the major slave holders became prominent political leaders in both the multiparty democracy period and the military dictatorship (1974 until 1991), and so the problem of slavery was largely ignored. In 2003, with pressure from the anti-slavery organization Timidria, Niger passed the first law in Western Africa that criminalized slavery as a specific crime. Despite this, slavery persists throughout the different ethnic groups in the country, women are particularly vulnerable, and a 2002 census confirmed the existence of 43,000 slaves and estimated that the total population could be over 870,000 people. The landmark Mani v. Niger case was one of the first instances where a person won a judgement against the government of Niger in an international court for sanctioning her slave status in official decisions.
Slavery existed throughout what is today Niger and the region played a pivotal role in the trans-Saharan slave trade for many centuries. In some ethnic groups, slavery became a significant phenomenon and made up a large part of the population and the economic production and trade. In other areas, slavery remained small and were only held by the elite in the communities. However, since political leaders often were slave-holders, they presented a significant hurdle for French authorities when they colonized the area and in post-independence Niger.
Much of the east of present-day Niger was involved in a significant part of the trans-Saharan slave trade with a route starting in Kano and traveling through the rugged Aïr Mountains. The Bornu Empire centered along this route became a prominent participant in the Arab slave trade prior to the Fulani jihad (1804–1808) to the east and the movement of Tuareg into the Aïr region in the 1800s. The trade through Bornu was small-scale for many centuries but remained steady before reaching its peak in the 1500s.