The coup against Khosrow II Preparations thumb|Map of the metropolis of Ctesiphon It was essential for the conspirators to move quickly to catch Khosrow II and his men off guard. To maintain contact between Ctesiphon and Veh-Ardashir, it was necessary to occupy the pontoon bridge over the Tigris River. The core of individuals involved in the conspiracy had to grow as quickly as feasible. To gather more support, they had to make the political equivalent of a shock attack. The conspirators agreed to stage the coup on the night of 23/24 February. They made the decision to inform Heraclius of the situation by sending a group of deputies to him. They required assurance that the Byzantines would be prepared to talk peace terms with a newly established Iranian government. They must have felt encouraged by Heraclius' recent proposition to Khosrow II, but they required a clear promise from him. Much justification for the coup attempt would be gone if there was no assurance that the Byzantines would also favor making peace, as the Sasanian state would get weakened by the coup.
The coup against Khosrow II Preparations thumb|Map of the metropolis of Ctesiphon It was essential for the conspirators to move quickly to catch Khosrow II and his men off guard To maintain contact between Ctesiphon and Veh-Ardashir it was necessary to occupy the pontoon bridge over the Tigris River The core of individuals involved in the conspiracy had to grow as quickly as feasible To gather more support they had to make the political equivalent of a shock attack The conspirators agreed to stage the coup on the night of 23/24 February They made the decision to inform Heraclius of the situation by sending a group of deputies to him They required assurance that the Byzantines would be prepared to talk peace terms with a newly established Iranian government They must have felt encouraged by Heraclius' recent proposition to Khosrow II but they required a clear promise from him Much justification for the coup attempt would be gone if there was no assurance that the Byzantines would also favor making peace as the Sasanian state would get weakened by the coup