In UNISON, Black is used to indicate people with a shared history. Black with a capital ‘B’ is used in its broad political and inclusive sense to describe people in Britain that have suffered colonialism and enslavement in the past and continue to experience racism and diminished opportunities today. More information can also be found at the below link.

https://www.unison.org.uk/about/what-we-do/fairness-equality/black-members/defining-black/

A copy of the leaflet can be found here.