He was a good one and is overlooked.

This guy is the best president of the United States never to actually be elected to the office, himself beginning his not-quite four year term after Garfield meets an assassin's bullet. Admittedly, that isn't saying much. But did you know, it could be argued that he, along with Admiral Mahan, is the father of the modern American Navy, the tool which, more than anything else, secured American dominance in the world. This makes him very important to the development of the USA in which we now live.