Centuries before the colonisers came, Christianity and Islam seeded a rich and ancient lineage in Africa

Every so often, a strange notion about religion in Africa comes forth: that neither Christianity nor Islam are African.

The thinking is that colonialists and Arabs brought these religions to Africa, converted Africans and thus mentally enslaved them with foreign ideas. Only by returning to "traditional" African belief systems can Africans be free, so the thinking goes.

Much is downright wrong with this notion. Even if this view of history is correct - in other words, even if we grant the notion for the sake of argument - it is highly insulting and quite rude.

Africa has roughly 500-million Christians and 400-million Muslims. According to the Pew Research Center, 60% of Christians and 63% of Muslims in Sub-Saharan Africa favour making laws reflecting biblical codes and sharia respectively. So, 900-million people are psychologically colonised?

However, neither slurs nor bad manners are illegal. They are, in fact, the hallmarks of free speech. Crass insults can also be true - but not in this case.

Many early Christian communities and pivotally important thinkers for the development of Christianity, such as Saint Augustine of Hippo (354-430), came out of North Africa. And not just North Africa: for example, the Kingdom of Abyssinia (in what is now Ethiopia) sent a delegation to the Council of Florence in 1441.

The long line of black Christian converts, martyrs and theologians - starting with the Ethiopian Enoch, described in Apostles Ch 8: 26-40, on to Saint Charles Lwanga (1860-1886) in Uganda and then the Rwandan Catholic priest Alexis Kagame (1912-1981) - should solidify the claim that Christianity is as African as it is European or Middle Eastern.

The Kebra Negast, written in Ge'ez in the 14th century, claims that the Ark of the Covenant was in Aksum and that the divinely favoured monarchs of Abyssinia could be traced back to the 10th century BC.

Predating Islamic Africa by 350 years, the Kingdom of Abyssinia provides more than 1,600 years of Christian moral and political philosophy, some of which is still relevant.

Zera Yacob (1599-1692), in his Hatäta, writes: "But today my countrymen have set aside the love recommended by the Gospel and turned away towards hatred, violence, the poison of snakes; they do things that are evil, so that they are falsely called Christians."

Usuman dan Fodio's Kitab al-Farq sparked a social and religious revolution in 1804. His indigenous and unique African interpretation of Islamic thought and, in particular, Sufism, resulted in a jihad that created the federal and theocratic Hausa and Fulani Sokoto Caliphate in Nigeria, which operated under Sunni Maliki jurisprudence. The caliphate covered 460,000km², took four months to cross from east to west, and lasted from 1810 to 1903, when the British forced its surrender.

Can we really say with a straight face that the Hausa and Fulani Sokoto Caliphate wasn't African? Nor can we deny that Timbuktu in Mali was an important centre of African Islamic learning. In 1665, a citizen of Timbuktu, Tarikh es Sudan es Abderrahman es Sadi, wrote a chronicle of Sudanese kingdoms.

Leo Africanus (1494-1554) states: "In Timbuktu there are numerous judges, doctors and clerics, all receiving good salaries from the king. There is a big demand for books in manuscript, imported from Barbary. More profit is made from the book trade than from any other line of business."

Putting the historical record of Islam and Africa in a different manner, it wasn't Arab forces that conquered Christian Spain in 711 but rather an Islamic army comprised mostly of Berber warriors. The army's general, Tariq bin Ziyad, was Berber. Africa successfully invaded the West 1,300 years ago.

The history of Africa is one of ideas and cultures travelling across the entire continent: the Sahara may be a physical boundary, but it has been a porous one. People and knowledge have moved up, down and across the Sahara for thousands of years. Africa's greatest philosopher, Frantz Fanon, specifically rejected the notion of a separate North and Sub-Saharan Africa.

Religions, philosophies and technologies from all over the world spread throughout Africa during the pre-colonial era and especially from city to city: Meroe, Kumbi Saleh, Djenne, Gao, Musumba, Mbanza-Kongo, Ryamurari, Kiguba, Mapungubwe, Gedi, Mombasa, Zanzibar, Great Zimbabwe and Kilwa Kisiwani.

The Zanj, a literate civilisation stretching from the ancient cities of Sofala, in Mozambique, to Mogadishu, in Somalia, started their conversion to Islam in the 8th century. In 1415, a Zanj delegation from Malindi, Kenya, arrived in Beijing and presented Emperor Zhu Di with a variety of gifts, including a giraffe. After the Portuguese destroyed Zanj cities, starting in 1497, the Zanj eventually became the Swahili.

To cast Christianity and Islam out of Africa's indigenous identity and pre-colonial history is to deny our humanity. Or, as the second-greatest African philosopher, Ibn Khaldûn (1332-1406), reminds us: "It should be known that history, in matter of fact, is information about human social organisation."

• Taylor is a South African political philosopher, thanatos.co.za