The left hand of destiny. Book 1 - J. G. Hertzler

The price of victory has been high. In the aftermath of the Dominion War, The Klingon General Martok, newly acclaimed Chancellor of the Klingon Empire, returns to the homeworld together with his adopted kinsman, Worf. They find a society splintered into factions and seething with unrest. Many Klingon warriors flock to Martok's banner, but his enemies are strong - chief amongst them his own bastard son
Rebellion, civil war and betrayal rock the Empire in this stirring tale of families riven by bitter conflict and a society poised precariously between redemption and dishonour.