richardson's 1st division played a key role during the battle of antietam on september 17, 1862, attacking confederate positions in the center of the sunken road in support of the 3rd division of maj. gen. william h. french. after stubborn fighting, by 1:00 pm, richardson had gained control of the high ground in front of the apex of the defensive line, and his men enfiladed the remaining defenders in the road, which would gain the nickname "bloody lane" for the carnage. richardson pushed forward beyond the road and was directing the fire of his artillery and organizing another attack when he was struck by a shell fragment.