Abu Bakr II (fl. 14th century), also spelled Abubakri and known as Mansa Qu, may have been the ninth mansa of the Mali Empire. He succeeded his nephew Mansa Mohammed ibn Gao and preceded Mansa Musa. Abu Bakr II abdicated his throne in order to explore "the limits of the ocean".
Abu Bakar was one of two sons of Cheikh Anta Diop, a sister of the founding emperor Sundiata Keita. He was the last of a mini-dynasty within the Keita clan of emperors descending from Kolonkan. After his abdication in 1311, the Faga Laye mini-dynasty would control the empire.
Virtually all that is known of Abu Bakr II is from the account of Chihab al-Umari. Al-Umari visited Cairo after Mansa Musa stopped there during his historic hajj to Mecca, and recorded a conversation between Musa and his host, Abu'l Hasan Ali ibn Amir Habib. According to Musa, Abu Bakr became convinced that he could find the edge of the Atlantic Ocean, and outfitted two expeditions to find it.
Following Abu Bakr II's failure to return from the second of those expeditions, Mansa Musa acceded to the throne.
The Arab-Egyptian scholar Al-Umari quotes Mansa Musa as follows:
The ruler who preceded me did not believe that it was impossible to reach the extremity of the ocean that encircles the earth (meaning Atlantic), and wanted to reach that (end) and obstinately persisted in the design. So he equipped two hundred boats full of men, like many others full of gold, water and victuals sufficient enough for several years. He ordered the chief (admiral) not to return until they had reached the extremity of the ocean, or if they had exhausted the provisions and the water. They set out. Their absence extended over a long period, and, at last, only one boat returned. On our questioning, the captain said: 'Prince, we have navigated for a long time, until we saw in the midst of the ocean as if a big river was flowing violently. My boat was the last one; others were ahead of me. As soon as any of them reached this place, it drowned in the whirlpool and never came out. I sailed backwards to escape this current.' But the Sultan would not believe him. He ordered two thousand boats to be equipped for him and for his men, and one thousand more for water and victuals. Then he conferred on me the regency during his absence, and departed with his men on the ocean trip, never to return nor to give a sign of life.
Ivan van Sertima and Malian researcher Gaoussou Diawara, proposed that Abu Bakr II traveled to the New World. Van Sertima cites the abstract of Columbus's log made by Bartolomé de las Casas, according to which the purpose of Columbus's third voyage was to test both the claims of King John II of Portugal that "canoes had been found which set out from the coast of Guinea [West Africa] and sailed to the west with merchandise" as well as the claims of the native inhabitants of the Caribbean island of Hispaniola that "from the south and the southeast had come black people whose spears were made of a metal called guanín ... from which it was found that of 32 parts: 18 were gold, 6 were silver, and 8 copper." Another supporting claim was made by Washington Irving, in his Life of Columbus, who wrote that in 1503 Columbus was on the Mosquito Coast. "There was no pure gold to be met with here, all their ornaments were of guanine; but the natives assured the Adelantado that in proceeding along the coast, the ships would soon arrive at a country where gold was in abundance".
However, many archaeologists, anthropologists, ethnohistorians, linguists, and other modern pre-Columbian scholars say that there is no evidence of any such voyage reaching the Americas, and that there are insufficient evidential grounds to suppose there has been contact between Africa and the New World at any point in the pre-Columbian era. For views representative of this point of view, see the considerations on the question advanced in Haslip-Viera et al. (1997), who for example note "no genuine African artifact has ever been found in a controlled archaeological excavation in the New World". See also the supporting responses in peer-review printed in the article, by David Browman, Michael D. Coe, Ann Cyphers, Peter Furst, and other academics active in the field. Ortiz de Montellano et al. (1997, passim.) continues the case against Africa-Americas contacts. Other prominent Mesoamerican specialists such as UCR Riverside anthropology professor Karl Taube are confident that "There simply is no material evidence of any Pre-Hispanic contact between the Old World and Mesoamerica before the arrival of the Spanish in the sixteenth century".
A BBC article titled "Africa's greatest explorer" summarizes the controversy from the perspectives of the scholars and historians in Mali.