This is what it is all about!

Gilead Prime is just another sprawling hive-world in the Calixis Sector. The Planetary Governor is old and in failing health. His nephew is bold, arrogant, and is really in charge. His nephew’s wife is strong willed, and has a scandalous past. The Chancellor is utterly corrupt, utterly ruthless, and virtually untouchable. The old noble families are spoiling for a chance to sieze power for themselves.

The Governor is the only man who has been able to keep the lid on this barrel of vipers. Without him, the planetary garrison may mutiny. The noble families’ private armies will do nothing to preserve Imperial rule. The Governor’s Successor has not yet been confirmed. The Chancellor is scheming, and fleecing, everything and everyone in sight.

. . . and the Governor’s health is failing.

Fast.

After that, take a look at your wiki. There is some more helpful info there.

Swords Around the Throne