From the forests of Atlantic Canada and northern Maine to the industrial corridors of western Pennsylvania, the ecosystems of the region, in contrast to the western United States, has been, according to Richard Judd, distinguished by  “the length, continuity, and intensity of Euro-American settlement.”1  As Matthew McKenzie2 pointed out more recently, “rather than a simple declensionist narrative chronicling the end of the frontier and the environmental legacies that ensued,” we should view the environmental history of this region more holistically, as a series oscillations: “deforestation and reforestation, depletion and renewal, settlements and abandonment, pollution and recovery.”3 
Add to these oscillations a long and complex social and cultural history dating from the end of the Pleistocene, shaped by an equally complex natural history of geological upheaval and climate change. Despite these oscillations – and possibly because of them – the region’s nineteenth century industrial economy encompassed a broad spectrum of humanized landscapes – farm and village, fishing, logging, textile, and shoe manufacturing centers, and lumber mill towns, among others.  In the twentieth century, the northeastern US and Atlantic Canada transitioned into financial services, high technology, medical sciences, and military procurement. Today, the economy of the New England region, the wealthiest in North America with a GDP of about $4 trillion, exceeds that of Germany.  
The humanized natural landscapes of the Northeastern US and Canada offer a rich field of opportunity for environmental historians.  Farms and factories, for example coexisted in nineteenth century in this eastern context, and Ellen Stroud has explored these interconnected urban and rural spaces. Challenging the often-repeated assertion that the region’s forests regenerated naturally after decades of clear-cutting, Stroud focuses on the crucial part dedicated citizens and governments played in protecting forests and promoting their return. She highlights the role of urban citizens “in creating and maintaining the new northeastern forests” and showing their “humanizing presence against the cliché of environmental decline that pervades so many environmental stories.”4 Being the first region in North America to experience reforestation should add to our definition of the region’s uniqueness. Judd points out that exploitation and conservation occurred simultaneously in the eastern US and Canada, and like Stroud argues that New Englanders pioneered some of the nation’s earliest grass roots conservation efforts. This conclusion again speaks to the Northeast’s uniqueness and its contribution to the larger environmental history framework. 
Historians have only begun to tap into this rich pre-settlement and post-settlement history; the northeastern region on both sides of the border includes dense metropolises, small industrial cities, rim cities, sprawling suburbs and exurbs, villages and towns. Waves of immigrants have passed through, leaving their own environmental imprint.
The NACEHF workshops over the past three years have begun to explore the environmental impact of these oscillations and negotiations in specific localities and/or regional contexts: as we move forward, we hope to further address the issue, creating perhaps a new paradigm for all environmental history based on the character of the land and people in the Northeastern United States and Atlantic Canada.  
Yet to be included in this paradigm are the region’s rivers, lakes, and estuaries – and the ocean environment that shapes coastal cultures on both sides of the border. Matt McKenzie has suggested that New England’s marine environment is easily as complicated as the story outlined above. Unlike the successes experienced on land over the region’s long history, the “marine realm still lies in a state of calamity.” (p.3) And as Matt has pointed out in the conclusion to his paper presented at the August 2, 2014 conference, human use of the North Atlantic marine resources came to a crashing halt in the mid-1990s. As a result, management of marine resources looks more akin to urban planning.  On land and at sea, opportunities and challenges await the environmental historian of the northeastern US and Atlantic Canada.