This island nation has been Islamic since the 16th century. French colonial rule was advanced in the decades between 1841 and 1912; political autonomy was not granted until 1961 and independence not until 1975. The president, Ahmed Abdallah Abderemane, was ousted that year by a mercenary force, though he returned to power three years later. In 1989, he was assassinated but the rebels responsible were forced to back down under French pressure. The 1990s brought a new constitution and the first democratic elections in 1992. Problems such as difficult weather, the lack of much arable land, and a poor infrastructure linking the islands has kept the Comoros underdeveloped.