The TomKat divorce was more than four years ago, but to refresh your memories...
...there was a TON of drama

Remember how Katie slowly moved her things into another apartment and completely pulled the wool over Tom's eyes? And then when he was stuck in Iceland filming a movie, she flew her lawyer dad in to New York and fired all of the handlers Tom hired for her

He was totally blindsided

And she filed for divorce in New York because it wasn't a no-fault state like California and she could sue for custody of Suri to keep her out of the hands of the Scientologists

They settled amicably and quickly - probably because neither Tom nor Scientology was ready to go through an extremely public legal battle with Katie that she would probably win.
The Brangelina breakup has iconic potential because this is the highest-profile, most glamorous movie star couple in the world and they have been ever since they got together. And the public attention is even more intense because Brad left Jennifer Aniston, America's Best Friend

to be with Angelina. Scrutiny over the stability of their relationship was so extreme because so many people felt loyalty to Jennifer. And more details surrounding the collapse of their marriage are still to come, bear that in mind
SO

Which breakup is going to go down as most iconic?
