Millennium is a Star Wars alternate history which ties in with the Daal saga, although it takes place over a larger time frame. It is mostly compatible with canon. However, a number of characters, places, events, etc have been added, and some of them may possibly come to contradict canon as it it added, and some events have replaced others. It describes the machinations of the Sith Lord Darth Tilentis in his quest to rule the Galaxy.
The Millennium was also the name of the Sith Order that, among others, Darth Tilentis belonged to (see Millennium (Sith Order)).