The Deed of Separation was significant in American colonial history as it marked the formal beginning of a political and administrative process that eventually led to the establishment of an independent United States. Signed in 1676, it allowed for a division between the colonies and their mother countries, asserting local governance and control. The Deed reflected the growing discontent among the colonies regarding British oversight and taxation. This step laid foundational ideas of self-determination and autonomy that fueled later revolutionary sentiments leading to independence from British rule in the late 18th century.