The San Francisco 49ers and Seattle Seahawks do not have a long, messy history. The two teams are divisional rivals, but it felt like, over the years, that the NFL was desperate to make the rivalry into something. They did the same thing with the 49ers and Arizona Cardinals when the Seahawks were still a bad team.
Darnell Dockett and Vernon Davis talking trash helped, but it never really amounted to much overall. Fans got into it here and there because these teams are divisional rivals, but I have to admit, I've never had much hate for the Seahawks.