Here is a list of the active effects being applied to each Order. These are temporary, only so far as certain triggers or requirements are met.
Global Relations
Dawn : Control of Avendor : Zealots +0.1
Griffons : Control of Sarleon : Loyalists +0.1
Silvermists: Control of Laria : Merchants +0.1
Eventide : Control of Nal tar : Merchants +0.2
Eventide : Control of Singal : Merchants +0.1
Order Upgrades
Note, Order Upgrades apply to all Order specific troops, so the Retainers, Order Knights, and Order Specials.
Dragon : Control of Senderfall : +1 Armour Quality (Armour)
Legion : Control of Cez : +1 Discipline (Foot Melee)
Eventide : Control of Ishkomman : +1 Ranged Weapon Quality (Foot Ranged, Mounted Ranged)
Order Boons
These are special powers that the Order can invoke under certain conditions.
Griffons : Control of Windholm : Recruit additional 300 Mercenary Vanskerry.
Dragons : Control of Ravenstern : Higher Morale in Battle.
Dawn : Control of Javiksholm : Produces one resource per turn for free (not gold)
Dawn : Control of Valonbray : One free Barque and two Galleys (Supply must be paid however)
Eventide : Control of Singal : Singal underworld buildings do not pay Influence.
Gauntlets : Control of Ethos : 25% chance that seriously wounded are returned to health.