The finances and financial administration of the Seleukid kings can be best understood against a historical background of the major events of their reigns, particularly those affecting the extent of their territory (and revenue), or requiring considerable military effort (and expenditure).

Seleukos I (311–281 bc)

The Seleukid empire is considered to have been founded with the return to Babylon, between 13 May and 3 June 311 bc, of Seleukos Nikator. That is how Seleukos' son, Antiochos (I), saw it when he inaugurated dating by the Seleukid era.

In 311 bc, Seleukos controlled hardly more than Babylonia, that is, southern Mesopotamia, and almost immediately faced a threat from Antigonos Monophthalmos, who had just concluded a peace treaty (311 bc) with his major rivals, Ptolemy, Kassandros and Lysimachos, and was now free to turn his attention eastwards. The subsequent war between the two Successors is not described in classical sources, but cuneiform documents attest to its ferocity, as Antigonos invaded Babylonia (310 bc) and ravaged the land. In 308 bc, in a critical battle, Seleukos was victorious and probably extended his rule into northern Mesopotamia at this time.

In the next few years, free from problems in the West, Seleukos marched east and took over, one by one, the satrapies of Alexander's empire that, in the turmoil of the clashes of the Successors, had been left free to fend for themselves.