Polygamy in Vedas
Krishna Yajur Veda 126.96.36.199
therefore as one goes many follow; therefore one becomes superior among many; therefore one wins many wives
Polygamy in Ithihas:
Mahabharata Adi Parva 1.160.36
There is no sin in this. For a man polygamy is an act of merit, but for a woman it is very sinful to betake herself to a second husband after the first.
Mahabharata Anusasana Parva 13.47
It has been laid down, O grandsire, that a Brahmana can take four wives, viz., one that belongs to his own order, one that is a Kshatriya, one that is a Vaisya, and one that is a Sudra, if the Brahmana wishes to indulge in the desire of sexual intercourse.
Many smritis allow Brahmin to have 4 wives, for a Kshatriya three, for a Vaishya 2 and for Shudra one. Now, is there any scripture which condemn polygamy?