Keith is a middle aged man with visa me wrinkles and eye bags. He has short black hair and is often rather grim looking. Typically he wears the standard uniform of the Survey Corps with a bolo tie.
In 844, one year prior to the fall of Wall Maria, Keith served as commander of the Survey Corps, and during this time, the Corps was in danger of losing funding for expeditions. Though dejected by the news, Keith could only accept the impending collapse of his regiment, but an intervention by the ambitious Erwin Smith would see the Survey Corps saved. Keith expressed shock that Erwin found a way to sway the political field, realizing the frightening potential and genius that Erwin possessed.At some point in time, Keith would cross paths with Levi. After being able to talk down to his other comrades and being unable to talk down nor "head butt" Levi, he would note that he did not need to meld him any more and from that point onward, people with "that look" within their eyes did not have to go through the Rite of Passage.
Later, Keith leads the Survey Corps on an expedition beyond the Walls. Keith is assigned to the front guard in the Long Distance Scouting Formation. While riding near a forest of giant trees, Keith and his squad spot a 15m Titan on the left. Keith orders for his squad to kill the Titan before it disrupts the formation. However, his squad fails to notice a 20m abnormal hiding in the trees. The Titan is later killed by members of Squad Flagon. After stopping for the night at a checkpoint, the Corps continues on the expedition. The formation is executed perfectly at first, until Keith notices storm clouds gathering above. Underneath the pouring rain, Keith orders for front guard to keep their eyes open.