Onyeka is a writer, law lecturer and historian. His books document the lives and history of the African experience in Britain. His work explores issues about cultural identity, resistance to oppression and the will to succeed.

Onyeka has written three novels, The Black Prince, Waiting to Explode and The Phoenix, which was awarded the 2009 African Achievers award for Communication and Media. He has also written three plays and his recent book, Blackamoores: Africans in Tudor England, their Presence, Status and Origins, is a ground breaking historical publication which highlights the significance of the presence of African people in Tudor England. This important work is based on the investigation of over 250,000 artefacts and documents gathered by the author, spanning more than 25 years of research. Some of this evidence was collected from archives and parish records across England and Europe.

Onyeka's latest play Young Othello is a drama set within an ancient African kingdom untouched by slavery or colonialism. It explores the natural and the mystical world to highlight human strength and weakness, and emphasises the uncontrollable passage of time. As the story unfolds, greed, jealousy and the thirst for power bring about the destruction of a nation and provide us with a deeper understanding of one of Shakespeare's most maligned characters.

Besides literature, Onyeka has worked with a variety of educational institutions including the University of London, Brunel, Southbank University, Queen Mary and Westfield, Birkbeck, Westminster, and the School of Oriental and African Studies. He has been a consultant and conducted project planning for government departments and ministers in the UK and abroad.

Onyeka's greatest work however, continues to be with the most vulnerable members of society and those most at risk of crime and social deprivation. Onyeka has worked tirelessly for more than 25 years, in deprived areas such as Tottenham, Peckham, Deptford, and Brixton, running community education programmes. These have included Black history courses, creative writing course, and personal development courses. He has given many lectures in schools, colleges and community halls. Onyeka has lent his expertise in law to desperate individuals, families and community groups who need legal advice. He has inspired thousands of his students to seek a better understanding about the world in which they live.