*please feel free to add to this if I missed anything significant.
1981 On the Fair Warning tour, Eddie approaches Billy Sheenan to join VH as the new bassist. Sheenan declines out of respect to Michael Anthony.
1993 While still in VH, Anthony and singer Sammy Hagar form a 'side band' called Los Tres Gusanos along with Hagar alum David Lauser on drums. The trio play Hagar's birthday bashes at Cabo Wabo in addition to other events.
1996 Anthony is suspicously removed from the writing credits to both "Jump" and "Panama" in the liner notes to VH's Best of Volume I, which also featured two new songs with original singer David Lee Roth.
1996 (Dec.) Upon the hiring of new singer Gary Cherone, rumours start of Anthony's exit/departure from VH. Eddie soon dispells the rumours as false.
1997 In his autobiography 'Crazy From the Heat', Roth states that Eddie was shopping around for bass players in order to remove Anthony from the band. This was during Roth's brief return to record two songs for Best of Vol. 1 in the summer of 1996.
1998 VH releases 'Van Halen III' with Cherone. The album becomes a commercial failure. Anthony is reportedly absent from much of the tracks, supposedly only playing on 3 of them. Anthony's trademark harmonies and backing vocals are also not heard.
2002 Anthony rejoins Hagar on stage for some dates on the co-headlining Sammy Hagar-David Lee Roth tour, to the dismay of both Eddie and Alex Van Halen.
2004 Hagar rejoins VH for a tour and records three new songs for another greatest hits compilation (BOBW). Anthony was not involved with either the writing or recording for all three songs. In a 2005 interview, Anthony claims that Eddie also did not want him for the tour. Hagar insisted he be involved and got his wish, however, as a consequence Anthony was paid considerably less than his fellow bandmates and had to relinquish several rights to the 'Van Halen' name and image. It is not clear whether song-writing credits were effected.
2005-2006 Hagar and Anthony tour as 'The Other Half'; self-proclaiming themselves to be 'the other half of Van Halen.'
2005 Anthony supposedly does not call Eddie and Alex to offer condolences on the passing of their mother. This upsets both Eddie and Alex greatly.
2006 Eddie confirms on Howard Stern that his son, Wolfgang, is the new bass player for Van Halen. Eddie also mentions being upset over Hagar and Anthony touring as 'The Other Half'; also referring to Anthony as 'sauce boy'.
2006 A press release confirms Anthony's replacement as Eddie's son, Wolfgang Van Halen.
2006 Roth is invited to rejoin and play with the new lineup. The band make preparations for a tour in 2007.
2007 Van Halen is inducted into the Rock and Roll Hall of Fame. The only people to accept the award in person are both former members Hagar and Anthony.
2007 (Aug) Van Halen announce their tour with Roth and new bassist Wolfgang Van Halen. VH.com is also updated, unfortunately with Anthony removed from the front covers of both Van Halen I (which also featured a 'photo-shopped' image of Wolfgang in his place) and WACF. Supposedly responding to the uproar from VH fans on the Internet, the albums are restored to their original form with Anthony.