[a] comprehensive and often revelatory history of American abolitionism from its origins in early colonial New England to its triumphant advance into the mainstream of the Republican Party before the Civil War.

...the seemingly endless detail presented over the course of nearly 600 pages of text and another 100-plus pages of notes frustrates her effort to present a clear alternative narrative to the familiar one ... Nonetheless, she has given us a full history of the men and women who truly made us free. And that is more than enough.

While the sheer amount of material seems to often overwhelm Sinha’s ability to elegantly present it as a narrative, she does offer fresh insights ... The Slave's Cause is as multifaceted as the movement it chronicles. Sinha includes lengthy thematic chapters on women in the fight and how abolition linked up — and clashed with — other reform movements. Sinha examines the heated debates over colonization efforts ... She also details how the movement responded to the Fugitive Slave Act

At once encyclopedic and analytically original, this massive tome – including back matter, the work swells to more than 700 pages – is a book of field-defining significance ... Sinha is at her best when she documents a vibrant and coherent intellectual tradition among African Americans ... Sinha’s treatment of the origins of the women’s rights movement reveals one of her book’s most glaring weaknesses (along with an occasional tendency to be somewhat ungenerous to previous generations of scholars who studied abolitionism and also to her peers now working in the field): inflexibility ... Sinha has nonetheless produced a powerful, ambitious work of scholarship. The research is extraordinary ... Her prose is also careful and often elegant, her argument bold ... Manisha Sinha’s book offers us a glimpse of a usable past: a diverse and inclusive story of abolitionism.

For the past half-century the abolitionists’ image has continued to improve, culminating in this prodigious work of scholarship ... This book is not for the faint of heart. Ten years in the making, its 275,000 words of text and 140 closely printed pages of endnotes are encyclopedic in both the positive and negative meanings of the word. Every antislavery organization that ever existed is here, listed by initials after the first mention ... While these and many similar paragraphs contain useful information, the reader’s eyes tend to glaze over. To cite an old cliché, it is often difficult to see the forest for the trees. Embedded among those trees, however, are several important motifs that add up to a comprehensive interpretation of the abolitionist movement ... Of all the names of abolitionists and antislavery politicians scattered through The Slave’s Cause—well over a thousand—one name is conspicuously missing, that of James Ashley, the congressman from Ohio who shepherded the Thirteenth Amendment to passage... Despite this omission, Manisha Sinha has cemented in place the last stone in the scholarly edifice of the past half-century that has rehabilitated the abolitionists’ reputation.

The Slave’s Cause plugs abolitionism back into the history of anticapitalist protest. In Sinha’s view, the abolitionists were critical of capitalism and 'sympathized with the plight of labor.' They insisted that there was a big difference between being whipped to work and being paid. But while decrying the 'robbery' of slaves’ labor, they warned that slavery also endangered the dignity and rights of white workers.

In The Slave's Cause readers have their fullest and most readable account yet of all his precursors and allies in the long struggle to bring about that impartial liberty in the teeth of opposition from very wealthy interests who believed they had God on their side. Sinha's big book deserves to become the new standard account of all those daring strivers.

Sinha does not neglect the white radicals. To the contrary, she expands the list of white activists to include a host of others, reaching back to the seventeenth and eighteenth centuries, such as Quakers, Mennonites, Puritans, and freethinkers. But her special contribution is to show that abolitionism was a 'radical, interracial movement' ... Sinha discusses even the most marginal voices in the abolition movement, such as enslaved people who sued their masters for freedom in the pre-1800 era, when some states granted legal rights to blacks ... One of the notable aspects of Sinha’s book is its subtle discussion of colonization, the white-led program to rid America of blacks, and emigration, the movement among blacks to exit the United States ... The breadth of Sinha’s book allows her to make the better-known aspects of abolitionism seem fresh ... What makes Sinha’s treatment original is that she gives voice to neglected reformers—many of them people of color and a good number of them women—who simultaneously made contributions to abolitionism even as the major figures were making the headlines ... Sinha unearths little-known African American and white radicals...

In The Slave’s Cause, she offers nearly 750 impassioned pages for considering abolitionism as a longstanding progressive force in American life ... Sinha’s history of the abolition movement is rich and comprehensive, even to a fault... for the most part, the drama of human struggle in the movement gets buried beneath the book’s encyclopedic level of detail. Sinha’s default narrative device is the summary list; her book thrums with ideas and arguments, but only the committed reader will stick it out.

Comprehensive survey of the abolitionist movement in Colonial and independent America ... Sinha’s capable but stolid; one wishes that more of, say, Jill Lepore’s or Doris Kearns Goodwin’s spirit pervaded the proceedings, especially in recounting the tangled politics underlying the Lincoln administration’s legislative accomplishments. Still, though it’s no Team of Rivals, the book covers a great deal of ground well ... Wide-ranging and admirably ambitious...