ARTABANUS IV., the last king of Parthia, was a brother of the preceding, and a son of Vologeses IV. According to Herodian, Caracalla entered Parthia in A. D. 216, under pretence of seeking the daughter of Artabanus in marriage; and when Artabanus went to meet him unarmed with a great number of his nobility, Caracalla treacherously fell upon them and put the greater number to the sword; Artabanus himself escaped with difficulty. Dio Cassius merely relates that Artabanus refused to give his daughter in marriage to Caracalla, and that the latter laid waste in consequence the countries bordering upon Media. During the winter Artabanus raised a very large army, and in the following year, A. D. 217, marched against the Romans. Macrinus, who had meantime succeeded Caracalla, advanced to meet him; and a desperate battle was fought near Nisibis, which continued for two days, but without victory to either side. At the commencement of the third day, Macrinus sent an embassy to Artabanus, informing him of the death of Caracalla, with whom the Parthian king was chiefly enraged, and offering to restore the prisoners and treasures taken by Caracalla, and to pay a large stun of money besides. On these conditions a peace was concluded, and Artabanus withdrew his forces.
In this war, however, Artabanus had lost the best of his troops, and the Persians seized the opportunity of recovering their long-lost independence. They were led by Artaxerxes (Ardshir), the son of Sassan, and defeated the Parthians in three great battles, in the last of which Artabanus was taken prisoner and killed, A. D. 226. Thus ended the Parthian empire of the Arsacidae, after it had existed 476 years. (D. C. 78.1, 3, 26, 27, 80.3; Herodian, 4.9, 11, 11, 15, 6.2; Capitolin. Macrin. cc. 8, 12; Agathias, Ilist. 4.24; Syncellus, vol. i. p. 677, ed. Dindorf.) The Parthians were now obliged to submit to Artaxerxes, the founder of the dynasty of the Sassanidae, which continued to reign till A. D. 651. [SASSANIDAE.] The family of the Arsacidae, however, still continued to exist in Armenia as an independent dynasty. [ARSACIDAE.]
The best modern works on the history of the Parthian kings are: Vaillant, Arsacidarum imperium sive regum Parthorum historia ad fidem numismatum accomodata, Par. 1725; Eckhel, Doctr. Num. Veter. vol. iii. pp. 523-550; C. F. Richter, Histor. Krit. Versuch über die Arsaciden und Sassaniden-Dynastie, Göttingen, 1804; Krause in Ersch und Gruber's Encyclopädie, Art. Parther.