Pan-Africanism is an ideology that aims to encourage and strengthen bonds of solidarity between all indigenous peoples and diasporas of Sub-Saharan African ancestry. Based on a common goal dating back to the Atlantic slave trade, the Trans-Saharan slave trade, the Indian Ocean slave trade, the Red Sea slave trade, slavery in the Cape Colony, Inboekstelsel, slavery in Mauritius, and the Khoikhoi-Dutch Wars, the belief extends beyond continental Africans with a substantial support base among the African diaspora in the Americas and Europe.

Pan-Africanism is said to have its origins in the struggles of the sub-Saharan African people against enslavement and colonization and this struggle may be traced back to the first resistance on slave ships—rebellions and suicides—through the constant plantation and colonial uprisings and the "Back to Africa" movements of the 19th century. Based on the belief that unity is vital to economic, social, and political progress, it aims to unify and uplift people of African ancestry. However, it was in the twentieth century that Pan-Africanism emerged as a distinct political movement initially formed and led by people from the Diaspora (people of African heritage living outside of the Continent). In 1900, the Trinindadian barrister – Henry Sylvester Williams – called a conference that took place in Westminster Hall, London to "protest stealing of lands in the colonies, racial discrimination and deal with other issues of interest to Blacks".

At its core, Pan-Africanism is a belief that "African people, both on the continent and in the diaspora, share not merely a common history, but a common destiny." Pan-Africanism posits a sense of a shared historical fate for Africans in the Americas, the West Indies, and on the continent, itself centered on the Atlantic trade in slaves, African slavery, and European imperialism.

Pan-African thought influenced the establishment of the Organisation of African Unity (since succeeded by the African Union) in 1963. The African Union Commission has its seat in Addis Ababa and the Pan-African Parliament has its seat in Midrand, Johannesburg.

Pan-Africanism stresses the need for "collective self-reliance". Pan-Africanism exists as a governmental and grassroots objective. Pan-African advocates include leaders such as Toussaint Louverture, Jean-Jacques Dessalines, Henri Christophe, François Duvalier, Aimé Césaire, Haile Selassie, Jomo Kenyatta, Edward Wilmot Blyden, Nnamdi Azikiwe, Patrice Lumumba, Julius Nyerere, Robert Sobukwe, Ahmed Sékou Touré, Kwame Nkrumah, King Sobhuza II, Robert Mugabe, Thomas Sankara, Kwame Ture, Dr. John Pombe Magufuli, Muammar Gaddafi, Walter Rodney, Yoweri Kaguta Museveni, grassroots organizers such as Joseph Robert Love, Marcus Garvey, and Malcolm X, academics such as W. E. B. Du Bois, Anténor Firmin and others in the diaspora. Pan-Africanists believe that solidarity will enable the continent to fulfil its potential to independently provide for all its people. Crucially, an all-African alliance would empower African people globally.^{[citation needed]}

The realization of the Pan-African objective would lead to "power consolidation in Africa", which "would compel a reallocation of global resources, as well as unleashing a fiercer psychological energy and political assertion ... that would unsettle social and political (power) structures...in the Americas".

Advocates of Pan-Africanism—i.e. "Pan-Africans" or "Pan-Africanists"—often champion socialist principles and tend to be opposed to external political and economic involvement on the continent. Critics accuse the ideology of homogenizing the experience of people of African ancestry. They also point to the difficulties of reconciling current divisions within countries on the continent and within communities in the diaspora.

As a philosophy, Pan-Africanism represents the aggregation of the historical, cultural, spiritual, artistic, scientific, and philosophical legacies of Africans from past times to the present. Pan-Africanism as an ethical system traces its origins from ancient times, and promotes values that are the product of the African civilisations and the struggles against slavery, racism, colonialism, and neocolonialism.