I think Elizabeth I hanging ( a slow process back then)of 20,000 Catholics a year topped the inquisition. Also the 50-60 million people that disappeared under Stalin topped it.
Priests were disemboweled alive by town butchers in England (that'll teach 'em) Oliver Cromwell killed over 1 million then he shipped 250,000 Irish to the Caribbean as slaves.
England's fire bombing of Hamburg and Dresden was worse than Hiroshima. the British pilots that flew in the raids referred to Major Harris, their commander, as a "mad dog".