The heir to the UK throne said the Commonwealth “must find ways, new ways, to acknowledge our past”.
Prince Charles has expressed deep "sorrow" over historical slavery in a speech to Commonwealth leaders in Rwanda.
The heir to the UK throne said the Commonwealth “must find ways, new ways, to acknowledge our past” and legacy for Indigenous communities.
"I want to acknowledge that the roots of our contemporary association run deep into the most painful period of our history," Charles told leaders at the opening ceremony in Kigali.
"I cannot describe the depths of my personal sorrow at the suffering of so many as I continue to deepen my own understanding of slavery's enduring impact."
“Quite simply, this is a conversation whose time has come,” he added.
Britain and other European nations enslaved millions of African citizens between the 15th and 19th centuries and transported them to plantations in the Caribbean and the Americas.
Commonwealth nations were meeting in Rwanda’s capital on Friday to tackle climate change, tropical diseases and other challenges deepened by the COVID-19 pandemic.
Some 32 of the Commonwealth’s members are small states, with 25 classified as vulnerable to climate change.
Charles attended to represent Queen Elizabeth II, who has restricted her official duties in recent years. The summit is taking place at an uncertain time for the British monarchy as well as the Commonwealth, whose relevance is sometimes questioned.
Elizabeth is currently the head of state of 14 Commonwealth realms, but Barbados cut ties with the monarchy in November, and several other Caribbean countries, including Jamaica, say they plan to follow suit.
In his remarks Friday, Charles said “free” nations can make such decisions “calmly and without rancour”.
But the summit in Rwanda will also consider applications by former French colonies Togo and Gabon to join the Commonwealth.
The decision to host the summit in Rwanda has also been criticised, given the country's poor human rights record.
The UK government has been widely condemned for signing a recent deal to transfer migrants thousands of miles to Rwanda for processing. That agreement faces legal hurdles, and the first group of migrants has yet to arrive in Africa.
Prince Charles has himself labelled the controversial policy as "appalling," according to UK media.