He was assasinated by an assasin aboard his ship. Before he died, he said "But it was so artistically done". The assasin's name was "Rukh" or "Juhk" or something like that.
Thrawn died during the climactic Battle of Bilbringi at the hands of his Noghri bodyguard, Rukh, who had discovered the duplicitous oppression of Honoghr for which Thrawn was responsible. Rukh crept up behind Thrawn as he was sitting in his command chair and stabbed him through the chest from behind the chair.
lightsabers, the force, grand admiral thrawn, boba fett, the emperor and Darth Vader. star wars rules
It was a New Republic victory despite heavy losses. Throughout most of the battle it actually looked like a pretty clear Imperial/Thrawn victory until Grand Admiral Thrawn was assassinated by his own bodyguard. Without Thrawn his second-in-command and successor (Gilad Pellaeon) lost hope and ordered a retreat, so the Bilbringi shipyards were occupied by the New Republic
The corresponding naval ranks are normally fleet admiral, grand admiral or admiral of the fleet.
War Admiral died in 1959.
Virginia Admiral died in 2000.
Himerios - admiral - died in 918.
Eric Rader
Admiral Schlei died on 1958-01-24.
Clas Fleming - admiral - died in 1644.
Edward Howard - admiral - died in 1513.
Erhard Schmidt - admiral - died in 1946.