After the death of Alexander, the great, his generals and high-ranking officials turned on each other in a series of wars called the Wars of the Diadochi. One of the largest participants in these wars was the Seleucid empire established by Seleucus.

Seleucus started out a small infantry commander of noble decent. He served alongside Alexander and was a major key to victory in multiple battles. For his actions Seleucus was promoted and led the best of the Macedonian infantry, the silver shields. Before Alexander died, he had many of his top officials and Generals marry Persian wives to blend Greek and Persian culture. However, after his death Seleucus was the only one of them to remain married to his wife, which boosted his popularity with the native population.

Fig.1  Simplewikipediea.com

Seleucus was a relatively small player in most affairs; he had very little influence compared to Alexanders other generals like Ptolemy, Antiochus, and Antigonus. Antiochus saw a use for Seleucus in his bid for power; so he made Seleucus the magistrate of Babylon. Seleucus and Antiochus had a very weak relationship. Nevertheless Seleucus helped him lead an invasion into Ptolemaic Egypt. This invasion failed however, due to the fact Antiochus was assassinated, most likely by Seleucus, in order to obtain more power.

After Antiochus was slain another one of Alexanders generals, Antigonus, came and dispelled Seleucus from Babylon. Seleucus then went to Ptolemy where he was given an army and took Babylon while Ptolemy and Antigonus were at war with each other. Seleucus started to conquer more and more territory at the expense of Antigonus. Eventually after years of constant war Antigonus was defeated and his territories conquered by Seleucus.

Fig.2 Historica.com

The new Seleucid empire became the largest of the successor kingdoms. After Seleucus died his empire was strife with constant invasions. With Gaul’s to the north, and Indians to the east, the Seleucids began losing bits and pieces of territory. Peace was made with the Indians by sending the rulers daughter to marry their king, after which this king gave the Seleucids over 500 war elephants which were used to great effect to defeat the Gaul’s in the north largely because they had never witnessed these animals before.

Fig.3 Weebly.com

The empire stayed stable for a few decades until the ruler died and the kingdom was riddled with civil wars, outside invasions and power struggles. During this time, the eastern provinces started to declare independence and formed their own kingdoms. The most prominent among these being the Parthians and the Bactrians. Antiochus III, a descendent of Seleucus  ended up getting the throne and reconquered almost all the territory that was lost. He also started to expand and take more territory until he too was stopped when he lost a decisive battle with the Romans. The Romans made the Seleucids pay heavy war debts and much of their treasury was emptied. Situations became worse when the Parthians raised an army and conquered most of the eastern empire.

The civil unrest ensued and became so bad that a group of Seleucids offered the crown to the king of Armenia, who promptly invaded the remaining parts of the empire. The Romans did not take to kindly to this, so they declared war on Armenia and pushed them out of Seleucia and propped up a puppet state that descended into one final civil war until the romans came and annexed the empire.