Re: King Solomon had 700 wives and 300 concubines
If you look at the historical context there was a political reason why Solomon took these women, and as one poster said before, many of these concubines represented a pact between Solomon and the hundreds of various kingdoms he made treaties with.
But I think, and this is just my speculation, much of it has to do with Solomon wanting to evoke a powerful masculine hegemony to the competing kingdoms who were hostile to him. These wives were a living representation of his personal and political virility. A king who has made alliances with hundreds of kingdoms is not a king you want to go to war with.
Many of the children born by these women were most likely sent back the home countries of their mothers to act as ambassadors, to cement relations, and to send back vital information as spies.
The Edomites, the Egyptians and Sheba all wanted a piece of Solomon's kingdom...if not outright subjugation of the Israelites. Solomon was not a warrior like his father David was. Solomon was a politician. So instead of waging war and overthrowing his neighbors, he made alliances and bought them off.