Answer:
The Declaration was written under the liberal and democratic thought, that's why its ideas spread and embedded in the Western outlook.
Step-by-step explanation:
This document was written in a period when several European kingdoms were losing their power and suffering from rebellions against their supposed divine origin. The Ancient Regimen was coming to an end, and the Declaration reflects these ideas of democracy, of a liberal and minimum state, where the individuals can live and thrive without being worry about the severe control of a State or a King. Most of it, I think, the thought of John Locke about the possibility to take down a government (legally) that doesn't comply with its duties, this idea of liberty is the most celebrated of all.