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Without Knute Rockne, there would be Notre Dame football. But without Rockne, there would be no legacy of winning, no subway alumni, no Four Horsemen, no Gipper speech, no Gipper president, no Notre Dame-USC rivalry, no Stadium that Rock Built -- a lot less thunder to shake down and barely any echoes to wake up. From 1918 through his premature death at age 43 in a plane crash in March 1931, Rockne led the Irish to five undefeated seasons. His record of 105-12-5 remains first in winning percentage (.881). The 1920s are known as the Golden Age of Sport. No list of the decade's athletic heroes -- Ruth, Grange, Jones, Dempsey, Tilden -- is complete without Rockne.