One of Vincent's regiments, the 20th Maine, led by Colonel Joshua Lawrence Chamberlain, has received most of the fame for the defense of Little Round Top, but there is little doubt that the efforts and bravery of Vincent were instrumental in the eventual Union victory. Vincent impressed upon Chamberlain the importance of his position on the brigade's left flank and then he left to attend to the brigade's right flank. There, the 16th Michigan Infantry was starting to yield to enemy pressure. Mounting a large boulder, Vincent brandished a riding crop given to him by his wife and shouted to his men "Don't give an inch!" A bullet struck him through the thigh and the groin and he fell. Due to the determination of the 20th Maine, the 44th New York, the 140th New York Volunteer Infantry Regiment, the 83rd Pennsylvania and the 16th Michigan Infantry, the Union line held against the Confederate onslaught. Vincent was carried from the hill to a nearby farm, where he lay dying for the next five days, unable to be transported home due to the severity of his injury.