Stories of the Japanese 00632 [Early Kamakura Period] The Jōkyū War: The Argument for Immediate Deployment

Oe Hiromoto likely anticipated that "the more time passes, the more the Imperial decree will spread throughout the country, increasing the number of enemies. Therefore, it is better to strike out now and deny the opposition time to prepare."
Miyoshi Yasunobu, also a civil official, agreed with this assessment.
While the decision to deploy was made, a consensus could not be reached regarding the timing. Hiromoto insisted on immediate departure, but Yasutoki proposed, "We should wait until our numbers have gathered. Why not march on the capital in two or three days?" He believed it would take time because the gokenin (vassals) needed to return to their lands to prepare before deploying.
Yoshitoki rebuked Yasutoki for his cautious approach and sided with Hiromoto's argument for immediate deployment, but because there were many dissenting opinions, no conclusion was reached regarding the timing of the departure.
Two days later, on the 21st day of the 5th month of Jōkyū 3 (1221), Ichijō Yoriuji (1198–1248) fled from Kyoto to Kamakura. Although Ichijō Yoriuji was of the Fujiwara clan, he had married a daughter of Hōjō Tokifusa and maintained good relations with the shogunate, so he likely felt his life was in danger.
Ichijō Yoriuji provided detailed reports on the situation in Kyoto, including the fact that warriors loyal to the Retired Emperor were gathering in the capital one after another, that Saionji Kintsune and his son Saneuji had been imprisoned, and that Iga Mitsusue had been driven to commit suicide. Upon hearing this, unease spread among the gokenin, and cautious opinions emerged, such as, "Perhaps there is no chance of victory even if we march on Kyoto."
However, Hiromoto insisted on deployment even more strongly, saying, "We decided to march on the capital, but because time has passed, opposition has arisen. Even now, if Yasutoki were to depart alone, the gokenin would surely follow one after another."
Miyoshi Yasunobu also agreed, stating, "If you have time to argue back and forth, you should simply dispatch the commander-in-chief immediately."
On the 22nd day of the 5th month, it was decided that Yasutoki would deploy as the commander-in-chief. It is said that before departing, Yasutoki visited Tsurugaoka Hachimangū and prayed, "If my march on the capital is not in accordance with reason, then take my life."
He must have had reservations about making the Imperial Court his enemy.
The force that left Kamakura with Yasutoki consisted of only 18 horsemen. The Azuma Kagami records that Tokifusa, Miura Yoshimura, and others followed shortly after, and that Eastern warriors continued to join them until the force eventually swelled to 190,000, though this is surely an exaggeration.