The other entities out there worshipped as gods are demons/fallen angels. Their worship may be a human construct but there are entities out there who will willingly move in behind the ideas.
They sacrificed to demons, which are not God - gods they had not known, gods that recently appeared, gods your fathers did not fear. Deut 32:17
I mean then that a sacrifice offered to an idol is anything, or that an idol is anything? No, but the sacrifices of pagans are offered to demons, not to God, and I do not want you to be participants with demons. You cannot drink the cup of the Lord and the cup of demons too; you cannot have a part in both the Lord's table and the table of demons. 1 Cor 10:19-21
The rest of mankind that were not killed by these plagues still did not repent of the work of their hands; they did not stop worshiping demons, and idols of gold, silver, bronze, stone and wood–idols that cannot see or hear or walk. Rev 9:20
They are spirits of demons performing miraculous signs, and they go out to the kings of the whole world, to gather them for the battle on the great day of God Almighty. Rev: 16:14
Jules