The incident occurred during a period of time very shortly after Hyōgo Port was opened to trade, and a day after the outbreak of fighting in Kyoto, leading to the Boshin war.
Because the port of Hyōgo had been opened on January 1, the troops advanced on the Saikoku Kaidō (西国街道) road rather than that built by the Tokugawa shogunate, in an effort to avoid encounters with enemy forces or foreigners.
The Japanese troops saw this as constituting tomowari (供割), an act of extreme disrespect under the Laws for the Military Houses, and Taki Zenzaburo, in charge of the third cannon group, took a spear and attempted to stop them.
The roadside skirmish soon also targeted the European and American dignitaries who were inspecting the adjacent planned site of a foreign settlement, and several full volleys were fired.
At this point in time, the Japanese imperial court had not yet informed foreign countries of the transition of power from the Shogunate to the Meiji government, and Itō Hirobumi attempted negotiations that quickly broke down.
There was some complaint that this was too harsh for an incident in which no one had actually died, and to the Japanese Taki's response to the foreign troops' tomowari seemed altogether natural, but in the face of a demand from the Great Powers there was nothing to be done.
Date Munenari sent an appeal for clemency via Itō Hirobumi and Godai Tomoatsu, which arrived just in time, but was rejected by a vote of the foreign ministers, beginning with the French Consul General Léon Roches.
Furthermore, this incident showed the court's foreign-relations philosophy turning quickly from that of "expel the barbarians" (攘夷, jōi) to "opening the country in peace and amity" (開国和親, kaikoku washin).