The Road to Babylon. Having accomplished his strategic goals in the west, Alexander renewed his pursuit of Darius for a third time. As Alexander marched through Syria en route to Babylon, Darius decided to cut his losses. He sent envoys to greet Alexander with conciliatory language and offers of peace. Darius promised to concede all lands west of the Euphrates River to Alexander if he would break off his attack against Persia (Diodorus Bibliotheca historica 17.54.1–2). Upon receiving this message, Alexander called a war council and presented them with the terms for peace. Parmenio, one of Alexander’s leading generals, replied, “If I were Alexander, I would accept these terms.” Alexander replied, “And so indeed would I, were I Parmenio” (Plutarch, Alex. 29.4). The tone of Alexander’s rebuff shows tension between the two; there is some evidence that Alexander was responsible for the later murder of Parmenio (Badian, “The Death of Parmenio,” 36–47). In any case, Alexander did not share in Parmenio’s reluctance to reengage the Persians. He ordered his generals to prepare for battle.

Darius was confident of victory. His forces greatly outnumbered Alexander’s, and he judged the Tigris too swift for the Macedonians to ford. He was wrong on both counts. Alexander rarely considered the odds when going to war, for he had often defeated armies much larger and better equipped than his. Darius also underestimated Alexander’s tactical ingenuity. To cross the swift Tigris, Alexander had his men form a human bridge by interlocking their arms one after the other until they reached the far bank (Diodorus Bibliotheca historica 17.55.3–6). He then ordered his remaining soldiers to clamber their way across this living bridge and prepare to meet the enemy.