I think the Crusades is the correct answer.
Collective nouns are always singular
Ex. A flock of birds is migrating to the South.
: I don’t see the poem could you tell me please
:
Onomatopoeia is a figure of speech which imitates sounds heard in nature. Having that in mind, the example of that figure in this poem would be moaning and groaning. The moaning and the groaning of the bells is a reference to the moaning and the groaning that animals and humans can produce.