Thrice Welcome

Thrice Welcome is the fourteenth soundtrack of The Hobbit: The Desolation of Smaug and indeed it is the main soundtrack through out the last two films.

Background
It is the background music in a few scenes:

The Hobbit: The Desolation of Smaug

 * The background music when Bard sails the Dwarves into Lake-town
 * Faintly appears when the Dwarves steal weapons from the armoury.
 * The background music when Thorin gives the speech to Master of Lake-town and Lake-towners about the treasures of Lonely Mountain.

The Hobbit: The Battle of the Five Armies

 * Faintly appears when Bard saves his children from an Ogre
 * The background music when Bard gathered the crowd to defend Azog's army in the Eastern Dale.

Appearances

 * The Hobbit: The Desolation of Smaug
 * The Hobbit: The Battle of the Five Armies