The story is told by Livy: in 172 BC, King Eumenes of Pergamon came to Rome, where the Senate received him with all pomp and fanfare the Romans believed to be due to one of their most loyal allies. The king had something to say indeed: he warned the conscript fathers that King Perseus tried to restore Macedonian power and might become dangerous.
After the summit, Eumenes returned to the east, making a brief stop in Cirrha, the port of Delphi, because he wanted to visit the sanctuary of Apollo. Apparently, Eumenes’ religious sympathies were well-known, because a Macedonian agent had sent assassins, who knew that the king would want to pay his regards to the god. They knew where to strike.
The report that the Macedonians had killed a king confirmed all suspicions against Macedonia and during the winter of 172/171, diplomats traveled everywhere to create coalitions for the war that had become inevitable. The Third Macedonian War lasted from 171 to 168 and was the end of Macedonia.
[Read more on the blog of Ancient History Magazine.]