Lagos
The exiled Oba Adele was still in Badagry when his successor, Oba Idewu, died. Prince Kosoko, Idewu Ojulari's brother, was a major contender for the now vacant throne. Eletu Odibo, the chief
kingmaker, thwarted Kosoko's aspiration and Adele was invited by him to become Oba again. Tinubu accompanied Adele to Lagos, but the Oba died 2 years later. After Adele's death in 1837, Tinubu reportedly supported Oluwole (her stepson) in his bid for the Obaship of Lagos over that of Kosoko's.[13][14]
Oba Oluwole had recurring conflicts with Kosoko, who felt that he was the true heir to the throne. Consequently, Kosoko was banished to Ouidah. During Oluwole's reign, Madam Tinubu remarried one Yesufu Bada, alias Obadina, who was Oluwole's war captain and with the support of Oluwole, Tinubu and Yesufu's trading activities in Egbaland grew.
When Oluwole died in 1841, Tinubu supported Akitoye (her brother in law) in his bid for the Obaship over Kosoko's.[13] After Akitoye emerged Oba, he granted Tinubu favorable commercial concessions.[11] Against the wish of his chiefs, Akitoye invited Kosoko back to Lagos and tried to placate him. Soon thereafter, Kosoko dislodged Akitoye from the throne. Considering Tinubu's alliance with Akitoye, she and other Akitoye supporters fled to Badagry when Kosoko became Oba in 1845.[16] As a wealthy woman, Madam Tinubu was able to influence economic and political decisions during her time in Badagry. She tried to rally Akitoye's supporters to wage war against Kosoko.
In December 1851 and under the justification of abolishing slavery, the British bombarded Lagos, dislodged Kosoko from the throne, and installed a more amenable Akitoye as Oba of Lagos. Though Akitoye signed a treaty with Britain outlawing the slave trade, Tinubu subverted the 1852 treaty[17] and secretly traded slaves for guns with Brazilians and Portuguese traders. Further, she obtained a tract of land from Akitoye which now constitutes part of the present-day Tinubu Square and Kakawa Street. Later, a conflict developed between Tinubu and some slave traders including Possu, a Kosoko loyalist. Consequently, Possu, Ajenia, and other traders tried to instigate an uprising against Akitoye because of Madam Tinubu's influence in Lagos. In the interest of peace, Benjamin Campbell, the British Consul in Lagos, asked Akitoye to exile Tinubu. After Akitoye died, Tinubu returned to Lagos and gave her support to his successor, Dosunmu. Under Dosunmu's reign Tinubu had a massive security force composed of slaves and she sometimes executed orders usually given by the king. As a result, Dosunmu grew wary of her influence in Lagos. A new development was the colonial government's support for migrants from Brazil and Sierra Leone to settle in Lagos. Many of the migrants, also called Saro and Aguda, were favored by the British in commerce and soon began dominating legitimate trade in Lagos.
In 1855, when Campbell traveled to England, Tinubu tried to influence Dosunmu to limit the influence of the returnees. Dosunmu was noncommittal to her request and consequently, Tinubu was alleged to have played a part in an uprising against the returnees in which her husband, Yesufu Bada, was a major participant. When Campbell returned in 1856, he asked Dosunmu to banish Tinubu. In May 1856, Tinubu was banished to Abeokuta.>[16]
Views on slavery
The often cited biography titled Madame Tinubu: Merchant and King-maker, authored by Nigerian historian Oladipo Yemitan, paints her views regarding slave trading.
On one occasion, during her final sojourn in Abeokuta, she was alleged to have sold a young boy into slavery and was accused of it. When arraigned before Ogundipe Alatise over the matter, she reportedly explained: 'I have a large house-hold and I must feed them well. I need money to do that, that's why'.
— Oladipo. Yemitan, 'Madame Tinubu: Merchant and King-maker'
Another section of Yemitan's Tinubu biography, referred to as the Amadie-Ojo Affair, captures a slave trading deal gone sour in 1853 (notably after the 1852 Treaty abolishing slavery in Lagos) wherein Tinubu tells another slave trader (Domingo Martinez) that "she would rather drown the slaves [20 in number] than sell them at a discount".