Originally published in 1919, this classic work of social psychology introduces the concept of the herd instinct in relation to human behavior and explores the fundamental importance of gregariousness among animals as well as among humans. In addition, author Wilfred Trotter incisively draws on the concept of social habit to provide a deeper understanding of the nature of human behavior as well as its affect on the national morale particularly in times of war. As Trotter noted in his original publication, these ideas may also be of use to a tired nation seeking peace.

From the onset of the modern civil rights and black power movements of the late 1960s and early 1970s through recent times, scholarship on Pennsylvania's African American experience proliferated. Unfortunately, much of it is scattered in books and journals that are not easily accessible. Under the editorship of Joe W. Trotter and Eric Ledell Smith, African Americans in Pennsylvania brings together an outstanding array of this scholarship and makes it accessible to a wider audience, including general as well as professional students of the black experience.

This volume, co-published with the Pennsylvania Historical and Museum Commission, offers the most comprehensive history of the state's black history to date. Chapters emphasize the interplay of class and race from the origins of the Commonwealth during the seventeenth century, through the era of deindustrialization in the late twentieth century. We see not only poor and working-class people but also educated business and professional people. And although scholarship has traditionally focused on the experiences of black men, this volume includes significant research on black women. Most important, this volume suggests a conceptual framework for a historical synthesis of the state's African American experience.

In his introduction, Trotter assesses the strengths and limitations of existing scholarship, showing how it is built on the contributions of nineteenth-century pioneers as well as those of the first generation of professional historians, including W. E. B. Du Bois, Richard R. Wright, and Edward Raymond Turner. Chapters are grouped into four interlocking parts that correspond to important changes in Pennsylvania's political economy. Each part includes a brief substantive introduction that ties together the themes of the ensuing chapters. This format enables readers to develop their own synthesis of key socioeconomic and political changes in the state's African American experience over more than three centuries of time.

African Americans in Pennsylvania shows how ordinary people have influenced the culture, institutions, and politics of African American communities in Pennsylvania. In the process, it documents the ways that black people have influenced, and continue to influence, the state as a whole.

Contributors are Elijah Anderson, John F. Bauman, R. J. M. Blackett, John E. Bodnar, Carolyn Leonard Carson, Dennis C. Dickerson, Gerald G. Eggert, V. P. Franklin, Laurence Glasco, Peter Gottlieb, Theodore Hershberg, Leroy T. Hopkins, Norman P. Hummon, Emma Jones Lapsansky, Janice Sumler Lewis, Frederic Miller, Edward K. Muller, Gary B. Nash, Merl E. Reed, Harry C. Silcox, Jean R. Soderlund, and Joe W. Trotter, Jr.