Banking was a recognized business in Babylon. This business was probably mainly in the hands of the priesthood. The banker was considered in the light of an agent or intermediary, borrowing money, not for himself, but for a third party. The taking of interest was allowed by law and the rate of interest was high. Twenty per cent, was the ordinary interest on a loan of money; when, as often happened, grain was lent to be repaid by grain, the rate would be much higher.

Many of the loans made by Babylonian bankers were upon the security of ships or cargoes, and we see here the beginnings of some of the existing principles of the modern law on this subject. The idea of the "bottomry" bond by which the lender, in consideration of an extra high rate of interest, loses his principal if the ship be lost, was recognized by the Babylonians. This perhaps represents the legal principle with the longest unbroken history.