On 28 October 1787, Thomas Clarkson pushed through the crowds to reach the pulpit of Manchester Cathedral. A campaigner for abolishing slavery, he spoke urgently about the horrors of the slave trade and the humanity of enslaved people. “He drinks the cup of sorrow,” Clarkson said. “And he drinks it at our hands.”

During Black History Month, these are the stories it is important to remember. They show us the complicated truth of our history. Thousands of people in Manchester signed a petition against slavery after Clarkson’s sermon. And yet Manchester’s cotton industry was built on the labour of enslaved people. There are similar stories up and down the nation. We are a country where brave people led the way in abolishing slavery, but we are also a country that participated in the trade in human lives.

The transatlantic slave trade was a brutal and barbaric violation of those people. They were denied their humanity. They were separated from their families, treated as property and worked to their deaths. I want to express my sorrow and regret for the pain and suffering of so many millions of people, and to recognise the way it still shapes our world today.

Our history is intertwined with countries that are now our allies, particularly in the Commonwealth. Next week, I will attend the Commonwealth heads of government meeting (Chogm). In an increasingly divided and dangerous world, our family of........

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