Seymour Cray was the Grand Old Man of classical supercomputing. He was the principal designer of the CDC 6600 and 7600, and left CDC to found Cray Research in 1973. After defining "supercomputing" in the public mind for over a decade, Seymour Cray left Cray Reserach in 1989 to start yet another company Cray Computer Corporation. Cray Research soldiered on without Seymour for another seven years, selling variants on the original Cray 1 design and the occasional Cray 2.
Eventually, Cray Research hit a rough patch financially and succumbed to overtures from Silicon Graphics Inc., accepting a merger that meant the end of Cray as a stand-alone computer company. At least for a while.
But in March 2000, SGI, now in great financial difficulty themselves, divested themselves of the Cray business, selling it to Tera Computer Company, who up until then had been selling supercomputers based on a multithreaded architecture developed by Burton Smith. Tera then renamed themselves Cray Inc.
So it's unclear whether we can really say that Cray is a dead supercomputer company. Either it was resurrected, or it was reincarnated.