It is bordered to the northeast by Tunisia ; to the east by Libya ; to the southeast by Niger ; to the southwest by Mali , Mauritania , and Western Sahara ; to the west by Morocco ; and to the north by the Mediterranean Sea. The capital and largest city is Algiers , located in the far north on the Mediterranean coast. Inhabited since prehistory , Algeria has been at the crossroads of numerous cultures and civilisations, including the Phoenicians , Numidians , Romans , Vandals , and Byzantine Greeks.
Its modern identity is rooted in centuries of Arab Muslim migration waves since the seventh century and the subsequent Arabisation of the indigenous populations. Following a succession of Islamic Arab and Berber dynasties between the eighth and 15th centuries, the Regency of Algiers was established in as a largely independent tributary state of the Ottoman Empire.
After nearly three centuries as a major power in the Mediterranean, the country was invaded by France in and formally annexed in , though it was not fully conquered and pacified until French rule brought mass European settlement that displaced the local population, which was reduced by up to one-third due to warfare, disease, and starvation.
Algeria gained its independence in The country descended into a bloody civil war from to Spanning 2,, square kilometres , sq mi , Algeria is the world's tenth-largest nation by area , and the largest nation in Africa. With a population of 44 million, Algeria is the tenth-most populous country in Africa, and the 33rd-most populous country in the world.
Algeria's official languages are Arabic and Tamazight ; French is used in media, education, and certain administrative matters, but it has no official status. The vast majority of the population speak the Algerian dialect of Arabic. Most Algerians are Arabs , with Berbers forming a sizeable minority. Sunni Islam is the official religion and practised by 99 percent of the population. Algeria is a semi-presidential republic composed of 58 provinces wilayas and 1, communes.
