English limitation law, set out primarily in the Limitation Act 1980, establishes maximum periods within which most civil claims must be brought. Contract claims: six years. Tort claims: six years, or three years for personal injury. No cause of action arising from events in the seventeenth, eighteenth, or nineteenth century could be brought in an English court under ordinary limitation rules.
There are equitable doctrines that can sometimes defeat limitation defences, and there are special rules for latent damage and deliberate concealment. But no court has ever applied these doctrines to extend limitation periods by centuries, and there is no realistic prospect of any court doing so for a slavery reparations claim.