Adam Clarke on Ezekiel 39:18

Ye shall - drink the blood of the princes of the earth - I need not mention the custom of the Scandinavians: they were accustomed to drink the blood of their enemies out of the skulls of the dead. But this is spoken of fowls and beasts here - rams, lambs, and goats. The feast shall be as grateful and as plenteous to the fowls and beasts, as one made of the above animals, the fattest and best of their kind, (because fed in the fertile fields of Bashan), would be to the guests of him who makes a sacrifice.