On 10 June, the Americans attacked the lightly defended
Choji Garrison on Ganghwa, along the
Salee River. The Koreans were armed with severely outdated weapons, such as
matchlock muskets, cannons, and
breech-loading swivel guns. After overrunning the Korean defenders, the Americans moved on to their next objective, the
Deokjin Garrison. American 12-pound
howitzers kept the poorly armed Korean forces from effective range. The American troops continued towards the next objective,
Deokjin Fort, which they found abandoned. The sailors and Marines quickly dismantled this fortress and continued to
Gwangseong Garrison, a
citadel. By this time, Korean forces had regrouped there. Along the way, some Korean units tried to flank the U.S. forces but were beaten off again due to the strategic placement of artillery on two hills. Artillery fire from ground forces and
Monocacy offshore pounded the citadel in preparation for an assault by U.S. forces. A force of 546 sailors and 105 Marines grouped on the hills west of the fortress (infantry troops were on the hill directly west of the fortress, while artillery troops on another hill both shelled the fortress and also covered the Americans' flanks and rear), keeping cover and returning fire. Once the bombardment stopped, the Americans charged the citadel, led by Lieutenant
Hugh McKee. The slow reload time of the Korean matchlocks aided the Americans, armed with superior Remington
rolling block carbines, in making it over the walls; the Koreans even ended up throwing rocks at the attackers. McKee was the first to make it into the citadel and was fatally wounded by a shot to the groin; after him came commander
Winfield Scott Schley, who shot the Korean soldier who had killed McKee. The flag of the Korean commander, General Eo Jae-yŏn, called the "
Sujagi" by Koreans, was captured by Corporal
Charles Brown of
Colorados guard and Private
Hugh Purvis of
Alaskas guard. General Eo was killed by Private
James Dougherty. While serving as the
color bearer for
Colorados crew and Marines,
Colorado Carpenter Cyrus Hayden planted the U.S. flag on the ramparts under heavy enemy fire. Corporal Brown, Privates Dougherty, Purvis, and Carpenter Hayden received the
Medal of Honor.The fighting lasted fifteen minutes. The total number killed was 243 Koreans and three Americans; McKee, Seaman Seth Allen, and U.S. Marine Corps Private Denis Hanrahan. Ten Americans were wounded, and 20 Koreans were captured, several of whom were wounded. Five Korean forts were taken in total, with dozens of small cannons. The Korean deputy commander was among the wounded who were captured. The U.S. hoped to use the captives as a bargaining chip to meet with local officials, but the Koreans refused, calling the captives cowards and "Low was told that he was welcome to keep the wounded prisoners." However, the Americans released the prisoners before departing. Following the military operations of 10–12 June, the United States
Asiatic Squadron stayed at anchorage off
Jakyak Island until 3 July, when they left for
China. ==Aftermath==