In my opinion, one of the most important songs from the 70s is that of Gordon Lightfoot's The Wreck of the Edmund Fitzgerald, released on his 1976 album, Summertime Dream. For those of you not familiar with the sinking of the SS Edmund Fitzgerald, the Fitzgerald was a bulk carrier freighter that sailed the Great Lakes. Launched in 1958, she was, for a time, the largest ship on those waters. On November 10, 1975, the Fitzgerald sank in 530 feet (162 m) of water near Whitefish Bay, Ontario, Canada, without having given any distress calls. All 29 men aboard died. The exact cause of the sinking is unknown. An excellent documentary by the Discovery Channel on the sinking of the Fitzgerald (which I have watched) suggests that three rogue waves in succession may have caused the Fitzgerald to take on water into the cargo holds before snapping the ship in half.
What's interesting about this song is the speed with which it was written and recorded. The Fitzgerald, as mentioned above, sank on November 10, 1975. The sinking was reported in a Newsweek article entitled "Great Lakes: The Cruelest Month," which was published on November 24th. Lightfoot used the article as his inspiration to write the song, which was then recorded in December, 1975.