I 1st wanted to instantly say The Attitude Era due to the fact that it was perhaps the BEST 4-5 years wrestling ever saw...BUT, then I thought about it further and realized that ECW was "attitude" before the WWF coined the phrase and even to a smaller extent, so was WCW. So with that said, I'd have to (sadly) say it was Hulkamaina. Without Hogan beating The Iron Shiek on Janurary 24, 1984, then the world of pro wrestling would have been drastically different. Hogan's impact on wrestling went beyond the ring, as everyone can attest to. The fact that Hogan, Vince & Piper came together to create WrestleMania means so much more than the Attitude for the simple fact that there'd have been no Mania's at all. In fact, it's sad that Hogan gets so much credit because Maina was created, in part, to Piper attacking Cyndi Lauper AND Hogan coming to her aid. No one paid to see Hogan & Mr. T, they paid to see Piper get beat up by Hogan. So with that said, Hulkamania was without a doubt, the BIGGEST impact on wrestling ever with the Attiude era coming in a close second.