An alliance formed in 1643 between the English colonies of Plymouth, Massachusetts Bay, Connecticut, and New Haven. This union was primarily established for mutual defense against Native American tribes, particularly the Pequot, Narragansett, and Mohegan. It also aimed to resolve boundary disputes and handle inter-colonial affairs more effectively. Each colony retained its own government, but the confederation provided a centralized structure for cooperation on matters of common concern.
The alliance marked an early instance of colonial unity and self-governance in British North America. It demonstrated the colonies’ capacity to organize and act collectively, independent of direct oversight from the British Crown. While the alliance faced internal tensions and disagreements, it served as a precedent for future cooperative endeavors among the colonies, laying the groundwork for eventual unified action during the American Revolution. The structure provided tangible benefits through coordinated military action and diplomatic negotiations, enhancing colonial security and stability.
