When Blight is Added, what order do you perform all of the effects of Adding Blight? If you were in the middle of a Ravage, do you finish the Ravage first?

When Blight is Added, what order do you perform all of the effects of Adding Blight? If you were in the middle of a Ravage, do you finish the Ravage first?

Do the ‘Immediately’ effects on the Blight card, and then finish resolving whatever caused the card to flip (whether it's a Ravage or something else).
More precisely, the order is:
  1. Take Blight off the card. If this empties the card, flip it, refill the Blight pool, and resolve any ‘Immediately’ effects on the card as a nested Action.
  2. Actually put the Blight in the land.
  3. Destroy Presence and do anything else that cares “when” this happens, like Kingdom of Sweden Level 5, Tsardom of Russia Level 1, or the Blight card All Things Weaken.
  4. If Blight was already present, cascade (returning to Step 1 in that adjacent land).
  5. Finish resolving the Action (usually the Ravage) that caused the Blight card to flip.
  6. Perform any Triggered Actions that care about Blight being added, like Kingdom of Scotland Level 5.
In particular, if more Invaders are added to the land being Ravaged (e.g., with Promising Farmlands), they don't deal more damage, as that step has already happened; however, they are susceptible to a Dahan counterattack, and any new Dahan (e.g., with Unnatural Proliferation) would participate.