Holy Trinity Church, Cloudesley Square by Stephen McKay under a CC licence
Tremors shook London on 8 February 1761 and then the following 8 March. A psychic predicted a greater earthquake would level London on 5 April which sent Londoners fleeing the city for the safe havens of Blackheath, Hampstead, Harrow and Highgate and Islington to avoid the destruction. They never came.
Islington may not have been a safe haven as buried in the churchyard of Holy Trinity Church, Cloudesley Square, was the quaking body of Richard Cloudesley, the Islington Ghost. On his death in 1517 Cloudesley bequeathed land to the parish, hence the church being on Cloudesley Square and there being a Richard Cloudesley school in Islington, the only school we know of in London that's named after a member of the undead.
Cloudesley left an additional legacy beyond his death, the ground around his grave shook and suffered "heavings, or tremblements de terre" because even then Islington couldn't have a simple earthquake.
There are many tales of holy ground not allowing a sinner to rest within it and the "wondrous commotion" and swelling earth were signs that Cloudesley's body was restless in the grave due to some un-confessed sin. "Certain exorcisers" went to the churchyard by torchlight at night to lay the "unruly spirit".
As a sign of his contribution to the parish, or just to be on the safe side, though, his remains were moved to a lead coffin in the church in June 1813 and placed under the weight of the church's vestry. And as far as we know Islington has not shuddered since.
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