The Archbishops of Canterbury and York were joined by thousands in a solemn procession of remembrance on Saturday to mark the bicentenary of the British Parliament's abolition of the slave trade.
The 'Walk of Witness' led by Dr Rowan Williams and Dr John Sentamu through the streets of London follows a vote last year by the Church of England's General Synod, that the Church should apologise for its role in the transatlantic trade.
In a lecture this week a senior Church of England bishop criticised evangelicals who backed the campaign to end the transatlantic slave trade as concerned primarily with saving the souls of slaves, but also highlighted how his predecessors justified the trade and opposed William Wilberforce's attempts to end it.
One of the church's voluntary missionary arms, the Society for the Propagation of the Faith in Foreign Parts, even owned the Codrington plantation in Barbados where slaves had the word "society" branded on their chests.
Addressing a rally in Kennington Park the Archbishop of Canterbury told more than 3,000 people, including foreign dignitaries and leaders of other churches: "The easiest thing in the world is to look back 200 years or 300 years and say we wouldn't have made those mistakes.
"A part of what we're doing today is recognising that the people who worked in the slave trade, people who kept going a system of inhumanity, were people like you and me. They were people who in many ways might of been decent, responsible people but they couldn't see."
The Archbishops have asked people to reflect on the horrors of the transatlantic slave trade.
They hope the 200th anniversary of the Act for the Abolition of the Slave Trade will prompt people to tackle the trade's legacies, including examples of human trafficking and oppression across the globe.
Campaigners also point out that Britain's still benefits from the wealth that the trade generated, whilst Africa still suffers in the aftermath.
Earlier, the procession, which began in Whitehall, saw the culmination of the March of the Abolitionists - a group of walkers who have worn yokes and chains during a 250-mile journey beginning in Hull.
They were released from their bonds by the Archbishop of the West Indies, the Most Rev Drexel Gomez.
The Archbishops of Canterbury and York led prayers on the south Embankment while holding a wreath marked with 2704, the number of ships which departed from London's docks to carry slaves during the Transatlantic slave trade.
The wreath was taken by boat towards the docks before being taken to Westminster Abbey for the national service to mark the Bicentenary on Tuesday.