Lagos was settled at various times by hunters and fishermen from the Àwórì sub-nationality. Originally based in Iseri on the Ògùn River about 20 miles from the island, the initial wave of settlers led by Arómiré ("the one that becomes personable at the sight of a

Lagos rests on the Gulf of Guinea. ()
river"), established a presence in Ìddó and Èbúté Métta. Arómiré also grew vegetables, especially pepper, on a site where Iga Ìdúngànràn, the palace or official residence of the Oba of Lagos now stands. Iga Ìdúngànràn is an Àwórì term meaning house on pepper farm. The palace is thus not only an important symbol of the historical traditions of Lagos; its name also helps keep alive the site's association with vegetable farming by Arómiré, the city's first settler.

From these bases the Àwórì settlers moved further south, towards the creeks and the sea. One major reason why they moved was because their increasing population created the need for more space. Another was safety and security. Yorùbáland, of which Lagos was a part, had become embroiled in the long-running wars involving ethnic groups, communities, chiefdoms, kingdoms, and other political units of the time. The island settlements faced war from the Ègbás and the Ìjèbús, both Yorùbá-speaking nationalities. The ancient Benin Empire, in present-day Edo State of Nigeria also invaded the island around the year 1600.

There are conflicting accounts of the latter episode. Some have argued that the Binis actually founded the Lagos monarchy or system of rulership, apparently in the image of Benin's. Ashipa, the first Oba of Lagos, was a Yorùbá chief but not a Lagosian. It is known also that between the sixteenth and nineteenth centuries, the Benin Empire extended as far as Porto-Novo, west of Lagos. The Oba of Benin did appoint viceroys or representatives on the island and approved all appointees to the office of Oba of Lagos. In return, Lagos Obas paid tribute to Oba of Benin in recognition of the latter's superior status. Other historians have insisted that the Oba of Benin waged war on the island for the same reasons wars were then prevalent.

One of these was the desire by reigning monarchs to expand control over weaker, less populous peoples or neighboring communities, kingdoms, and empires. Another reason concerned the new trans-Atlantic slave trade. For those who participated in the trade as middlemen, warfare did provide a quick and sure supply of war captives who could then be sold as slaves and shipped to the New World. By an estimate, some 500,000 people may have been sold as indentured slaves and shipped from Lagos to the Americas and the Carribean, in particular Bahia, Cuba, and St. Helena. Anyway, for Arómiré and early settlers of the island, moving further south away from the mainland towards the sea was a mechanism to escape the wars that ravaged Yorùbáland from the seventeenth century. The wars and the disruptions associated with them were to become a justification for imposing British colonial control first on the island and later on what is now Nigeria.

From the mid-nineteenth century, freed Yorùbá slaves started returning to Lagos in waves first from Brazil and then from Sierra Leone. In 1847, Oba Kòsókó of Lagos sent his close friend and adviser Chief Oshòdì Tápà to South America to invite slaves with Yorùbá ancestry to return home. The trip yielded results in 1851 when 130 expatriates arrived in Lagos. By 1861 when Lagos formally became a British colony, the number of returnees had risen to about 3,000. The Brazilian expatriates brought with them skills in masonry, carpentry, and tailoring, a strong Catholic faith, and extensive Portuguese cultural traits.

Sierra Leonean expatriates, or Saros, mainly of Ègbá origins in present-day Abéòkúta in Ògùn State of Nigeria, started returning to Lagos in trickles about 1838. The reigning Oba Kòsókó did very little to make them feel welcome, so it was not until 1852 after Oba Kòsókó had been deposed by the British and replaced by Oba Akíntóyè, that Saros returned to Lagos in large numbers. They numbered about 2,500 by 1861 and were granted land in a district on the island still known as Saro Town.

With their longer association with English missionaries, Sierra Leonean returnees appeared to enjoy higher standards of material comfort than Lagos indigenes. The Saros were devout Protestants and better educated in the formal sense too. These attributes were to stand them in good stead to play a leading role in the cultural life of Lagos; they also helped infuse their fatherland with a love of education. Their efforts were to help create a class of literate indigenes who led the fight for human dignity under British colonial rule and set the stage for the nationalist struggle that led to Nigeria's independence in 1960.

These main groups have since been joined by a more heterogeneous mix of immigrants from far and near. The Vaughan family has American ancestry while the Bickersteth family originated from Porto-Novo in present-day Benin Republic. Lagos is also home to people with Ghanaian ancestry. A much larger number have moved south over the years from other parts of Nigeria—for example, from the Nupe and Benin areas in addition to Yorùbá migrants, especially from Ìjèbú, Ègbá, and Badagry areas.