Bird in Danzig Rebellion (5)
I believe the answer is:
grebe
'bird' is the definition.
(type of bird)
'in danzig rebellion' is the wordplay.
'in' indicates the answer is hidden within the clue.
'GREBE' can be found hidden inside 'danzig rebellion'.
(Other definitions for grebe that I've seen before include "Duck-sized water-bird" , "Diving waterbird" , "Diving bird which may be crested" , "Crested water-bird" , "Small diving waterfowl with a long neck" .)