It looks like a weekend Steam sale started yesterday at 75% off for all of the of the total war titles except Warhammer, which is 33% off.

This means all of their historical titles, most of which were already reduced in price since they are not new any more.

Shogun 2-------$7.50 This and FOTS plus most of unit packs can be had together for $10 total.
Shogun 2 FOTS--$7.50
Rome 2-------- $15.00
Attila---------$11.24
Napoleon-------$5.00
Empire---------$5.00

These don't include any culture packs of mini-campaigns except for Rome 2, since the Emperor Edition also comes with the Augustus campaign and the combo deal for Shogun 2 main and Fall of the Samurai stand alone expansion

Cheers

Artillery adds dignity to what would otherwise be a vulgar brawl.