Number 2 (in Notre Dame and perhaps college football history): Frank Leahy
His .864 winning percentage (87-11-9) is bested only by Knute Rockne. His innovative "T-formation" offense changed the game of football forever. A former tackle on Rockne's teams of the late 20s, Leahy was an ambassador of the grand Notre Dame tradition in the finest sense, capturing four national championships, an incredible six undefeated seasons (four with a tie), and went on a ridiculous 39-game unbeaten streak in the late 40s (that included two ties).
In addition, he coached four Heisman Trophy Winners and took part in one of the greatest games in college football history, the 1946 0-0 tie against a then-powerhouse Army squad; a battle that gave the Irish a national championship. A solid argument could be made that Leahy is the greatest coach in college football history (especially when considering the "era" factor), but on this list Coach Leahy comes in at Number 2, not surprisingly because of:
Number 1: Knute Rockne
Let's put the statistics aside for a second. Rockne is a figure of culturally historic proportions. A figurehead of the Roaring Twenties on a level with Babe Ruth and Charles Lindbergh, Knute played a major role in shaping the national entity that college football is today. Barnstorming his squad around the country, including to the West Coast to play teams like Southern California, Knute was a marketing genius, transforming college football into a sport with nationwide appeal and recognition and Notre Dame into its most recognizable brand.
Without Knute, the sport's growth would have been greatly stunted — struggling to break free from its largely midwestern confines — and the small Catholic school in the small Indiana town of South Bend would never have become home of the most storied football team in the history of the game.
On the sidelines, Rockne was peerless in his success. In his 13 years as head coach of his alma mater Rockne posted an all-time best 105-12-5 record (that's winning 88.1% of his games, folks) and collected six national championships and five undefeated seasons with teams that included George Gipp, the Four Horsemen, and Frank Leahy.