In general, why was the Declaration of Independence written?

It was to make piece between the everyone in the us. Once signed they had decided that the us should be made and combined once and for all

General:

The Declaration of Independence declared the colonies' independence from Great Britain.

Specific:

It started with the Preamble, which listed the inalienable rights that the colonists felt were important. It also listed the reasons the colonists thought the British were being unfair.