Odaenathus formed an army of Palmyrenes and Syrian peasants against Shapur.
According to the Augustan History, Odaenathus declared himself king prior to the battle.
The Palmyrene leader won a decisive victory near the banks of the Euphrates later in 260 forcing the Persians to retreat.
In 261 Odaenathus marched against the remaining usurpers in Syria, defeating and killing Quietus and Balista.
As a reward, he received the title Imperator Totius Orientis ("Governor of the East") from Gallienus, and ruled Syria, Mesopotamia, Arabia and Anatolia's eastern regions as the imperial representative.
Palmyra itself remained officially part of the empire but Palmyrene inscriptions started to describe it as a "metrocolonia", indicating that the city's status was higher than normal Roman colonias.
In practice, Palmyra shifted from a provincial city to a de facto allied kingdom.

In 262 Odaenathus launched a new campaign against Shapur, reclaiming the rest of Roman Mesopotamia (most importantly, the cities of Nisibis and Carrhae), sacking the Jewish city of Nehardea, and besieging the Persian capital Ctesiphon.
Following his victory, the Palmyrene monarch assumed the title King of Kings.
Later, Odaenathus crowned his son Hairan I as co-King of Kings near Antioch in 263.
Although he did not take the Persian capital, Odaenathus drove the Persians out of all Roman lands conquered since the beginning of Shapur's wars in 252.
In a second campaign that took place in 266, the Palmyrene king reached Ctesiphon again; however, he had to leave the siege and move north, accompanied by Hairan I, to repel Gothic attacks on Asia Minor.
The king and his son were assassinated during their return in 267; according to the Augustan History and Joannes Zonaras, Odaenathus was killed by a cousin (Zonaras says nephew) named in the History as Maeonius.
The Augustan History also says that Maeonius was proclaimed emperor for a brief period before being killed by the soldiers.
However, no inscriptions or other evidence exist for Maeonius' reign.

Odaenathus was succeeded by his son; the ten-year-old Vaballathus.
Zenobia, the mother of the new king, was the de facto ruler and Vaballathus remained in her shadow while she consolidated her power.
Gallienus dispatched his prefect Heraclian to command military operations against the Persians, but he was marginalized by Zenobia and returned to the West.
The queen was careful not to provoke Rome, claiming for herself and her son the titles held by her husband while guaranteeing the safety of the borders with Persia and pacifying the Tanukhids in Hauran.
To protect the borders with Persia, Zenobia fortified different settlements on the Euphrates including the citadels of Halabiye and Zalabiye.
Circumstantial evidence exist for confrontations with the Sasanians; probably in 269 Vaballathus took the title Persicus Maximus ("The great victor in Persia") and the title might be linked with an unrecorded battle against a Persian army trying to regain control of Northern Mesopotamia.
Odaenathus formed an army of Palmyrenes and Syrian peasants against Shapur. According to the Augustan History, Odaenathus declared himself king prior to the battle. The Palmyrene leader won a decisive victory near the banks of the Euphrates later in 260 forcing the Persians to retreat. In 261 Odaenathus marched against the remaining usurpers in Syria, defeating and killing Quietus and Balista. As a reward, he received the title Imperator Totius Orientis ("Governor of the East") from Gallienus, and ruled Syria, Mesopotamia, Arabia and Anatolia's eastern regions as the imperial representative. Palmyra itself remained officially part of the empire but Palmyrene inscriptions started to describe it as a "metrocolonia", indicating that the city's status was higher than normal Roman colonias. In practice, Palmyra shifted from a provincial city to a de facto allied kingdom.
In 262 Odaenathus launched a new campaign against Shapur, reclaiming the rest of Roman Mesopotamia (most importantly, the cities of Nisibis and Carrhae), sacking the Jewish city of Nehardea, and besieging the Persian capital Ctesiphon. Following his victory, the Palmyrene monarch assumed the title King of Kings. Later, Odaenathus crowned his son Hairan I as co-King of Kings near Antioch in 263. Although he did not take the Persian capital, Odaenathus drove the Persians out of all Roman lands conquered since the beginning of Shapur's wars in 252. In a second campaign that took place in 266, the Palmyrene king reached Ctesiphon again; however, he had to leave the siege and move north, accompanied by Hairan I, to repel Gothic attacks on Asia Minor. The king and his son were assassinated during their return in 267; according to the Augustan History and Joannes Zonaras, Odaenathus was killed by a cousin (Zonaras says nephew) named in the History as Maeonius. The Augustan History also says that Maeonius was proclaimed emperor for a brief period before being killed by the soldiers. However, no inscriptions or other evidence exist for Maeonius' reign.
Odaenathus was succeeded by his son; the ten-year-old Vaballathus. Zenobia, the mother of the new king, was the de facto ruler and Vaballathus remained in her shadow while she consolidated her power. Gallienus dispatched his prefect Heraclian to command military operations against the Persians, but he was marginalized by Zenobia and returned to the West. The queen was careful not to provoke Rome, claiming for herself and her son the titles held by her husband while guaranteeing the safety of the borders with Persia and pacifying the Tanukhids in Hauran. To protect the borders with Persia, Zenobia fortified different settlements on the Euphrates including the citadels of Halabiye and Zalabiye. Circumstantial evidence exist for confrontations with the Sasanians; probably in 269 Vaballathus took the title Persicus Maximus ("The great victor in Persia") and the title might be linked with an unrecorded battle against a Persian army trying to regain control of Northern Mesopotamia.
Palmyra