Julian’s desire to avenge the frontier regions which had suffered from the recent Persian incursions and his refusal to discuss peace with an embassy from Persia: Libanius or. XVII, 19 and XVIII, 164. His boast that he would restore Singara: Ephrem, Hymni Contra Julianum II, 15. (On his refusal to defend Nisibis on account of its citizens’ loyalty to the Christian faith, see Sozomen, V, 3, 5=ELF 91). He commanded Arsak (Arsaces), the king of Armenia, to muster a large army and to join him later at a place to be designated: Amm. XXIII, 2, 2, Lib., or. XVIII, 215 and Soz., VI, 1, 2.1 He ordered ships to be built in Samosata: Malalas, XIII, pp. 328, 21-329, 2 (=Magnus of Carrhae, FGrH 225, F 1). His enquiries at various famous oracles: Theodoret, Historia Ecclesiastica III, 21, 1-4. His intention to establish Hormisdas as ruler of Persia: Libanius, ep. 1402, 3. See also Libanius, ep. 737, 1-3 for an example of Roman optimism concerning the campaign.