Immersing himself in the "new labor history", he researched and wrote a series of community studies about railroad workers, coal miners and ironworkers.
During his earliest years as a labor historian, Gutman's thesis was that "workers derived their strength from their small-town milieus and from alliances with class elements unsympathetic to the rising industrialists ..." But, as he later admitted, this conclusion was wrong.
The lectures attracted widespread attention from unions, workers and Gutman's peers for their engaging style, detail and application to current events in the labor movement.
The enthusiasm generated by the NEH lectures led Gutman to co-found the American Social History Project at CUNY Graduate Center.
It produced a film, a series of slide shows, and a two-volume history of working people in the United States entitled Who Built America?
He is considered one of the co-founders and primary proponents of the "new labor history," a school of thought that believes ordinary people have not received the proper amount of attention from historians.
[4] He developed a critique of the "Commons school" of labor history that focused on markets and minimized other factors such as technological or cultural changes and working people themselves.
"[5] Gutman was often criticized for overemphasizing the experiences of working people and blacks as historical agents, and "sometimes summarily dismissed as a 'romantic' and lacking in sophisticated 'theory'…".
In Slavery and the Numbers Game, Gutman argued that Fogel and Engerman chose their examples poorly, focussing on plantations which were unreflective of broader southern society.
Gutman roundly criticized Fogel and Engerman on a host of other claims as well, including the lack of evidence for systematic and regular rewards and a failure to consider the effect public whipping would have on other slaves.
Gutman also argued that Fogel and Engerman had fallen prey to an ideological pitfall by assuming that most of those enslaved had assimilated the Protestant work ethic.
It not only constituted an excellent example of social history for its focus on individuals but it challenged long-held conventional ideas about the slavery's effects on black families.
[4] Here, Gutman wrote in opposition to previous approaches to U.S. working-class history that had focused on trade unionism, instead examining "the institutions, beliefs, and ideas that American workers ... created and recreated in their adaptation to the harsh realities of the new industrial system.