1995 for me. I didn't grow up in Ohio, we moved here from Germany in 1995.
I grew up in Michigan (until 1992) & was a Notre Dame fan for their tradtion & (then) excellence. Notre Dame games were actually broadcast in Germany & I watched The Irish there too. I'm proud to say I've never been a Michigan fan.
Then we moved here & two things happened that year: 1.) The Buckeyes thumped the Irish; 2.) Eddie George had that amazing Heisman season. I was hooked.
Then I went to Ohio State & was locked in for life, of course.