Vampire the Masquerade says there are 13 clans of Vampires, each descended from one of the 13 Antediluvians. VTM5e backstory says that vampires appeared about 6,000 to 10,000 years ago, and all 13 clans (if I'm reading it right) seem to have been up and running in Biblical times.The Tremere clan, however are latecomers, only becoming vampires many centuries later.
VTM5e names 13 clans. Namely these 7 (as PC clans):
- Brujah;
- Gangrel;
- Malkavian;
- Nosferatu;
- Toreador;
- Tremere;
- Ventrue.
And then these ones on page 63, where it mentions:
- Lasombra;
- Tzimisce;
- Giovanni;
- Ravnos;
- Banu Haqim;
- Setite Ministry.
There are also some references to a 14th clan (the Guruhi, dominant clan in Africa), but it says they share an ancestor with the Nosferatu.
Finally, the question... Who were the 13th clan in the centuries before the Tremere were created? The Guruhi? The Salubri bloodline from earlier editions of VTM? Something else?