Well Blackwolves are said to be the 1st jj2 clan established, and as far as I know it the only one never to have been beaten. Although I think there were some other clans like that, as a lot of clans hardly do/did wars. Anyway they PWNT in 98, but soon got tired of jj2 I suppose.
It should also be noted that in 99 there was a serverlists cash(more of them I think), so a lot of players stopped jj2ing never to return. I got back to jj2 in late august, when I found out, by chance, that jj2 is still functional.