Attempts to exert influence on the conservation charity have been vigorously resisted but it remains vigilant

Corinne Fowler remembers sitting alongside her son in their garden shed during the first Covid lockdown, when the very start of what would become an avalanche of hate mail popped up in her inbox.

“There was a barrage of emails but the first one just said in the title: ‘You’re cooked.’ And it went on from there,” recalls the historian, who in 2020 had just published a landmark report into the colonial history behind some National Trust properties.