Irish freemasonry has long suffered from a lack of sustained academic attention. While historians such as Nancy Curtin and Kevin Whelan have suggested that freemasonry was a shaping force in the popular political movements of the late eighteenth and early nineteenth centuries, the study of masonic history has largely been left to popular writers and the masons themselves. In Freemasonry in Ulster, 1733–1813, Petri Mirala begins the work of correcting this oversight by examining the development of freemasonry between the founding of the first masonic lodge in Ulster in 1733 and the movement's decline in the early nineteenth century. Using masonic records in conjunction with government papers, contemporary publications, and other sources, he moves beyond modern assumptions about eighteenth-century masonry and reveals it to be an extensive and varied phenomenon with connections to a wider world of male sociability.

Mirala argues that Irish freemasonry was an unusually powerful and widespread movement extending beyond the metropolitan centers. Although the freemasons are often thought of as a secret organization, masonic lodges played a prominent role in their local communities. Particularly in the countryside, where there were few other clubs or societies, masons provided much-needed social activity. While the masons occupied themselves with rituals and homosocial conviviality, they also put on parades and other entertainments that the wider public could enjoy. As important, the masonic lodge provided its members and their families with a source of relief in times of distress; depending on the attitude of the lodge involved, nonmembers could also benefit from masonic charity.

While Mirala's investigation into the composition of the masons results in no definite figures, he draws several conclusions. Although the expenses associated with being a mason should have ensured that all masons were “respectable” men, the social rank of incoming members declined over the course of the period. The masons were well aware of social distinctions, and some of their lodges were divided up accordingly. While some lodges excluded Catholics, there were many Catholic masons, and their numbers increased greatly in the last quarter of the eighteenth century. Furthermore, in addition to the regular masons, whose lodges were endorsed by the Grand Lodge in Dublin, there were numerous groups of unofficial “hedgemasons,” who came from the lower classes and formed their own lodges without authorization.

After addressing the variety of people within the masonic movement, Mirala adopts a cautious approach when considering the link between masonry and popular politics. He argues that Ulster masons may have first involved themselves in political reform with the 1776 general election. Some masons also became involved with the Volunteer movement in its later stages, but the degree of participation varied from region to region. Nevertheless, Volunteers and masons shared some similar characteristics, such as the use of coded gestures. Mirala speculates that the politicization of American lodges during the American Revolution may have prompted some of Ulster's lodges to do likewise. However, he also observes that masonry was supposed to be apolitical and cannot be automatically equated with a reformist ideology. Although masons became more widely involved in political matters during the 1790s, the movement adopted no single view toward the issues of parliamentary reform or Catholic relief. Lodges ranged from the conservative to the radical, and some changed their political orientation over time. Mirala notes that some masons were United Irishmen, but he dismisses arguments that the masons served as a front for the group or that the United Irishmen might have imitated the masons’ organizational structure. However, Mirala argues that the Defenders, whose members included both regular masons and hedgemasons, did derive some of their traits from masonry and may even have thought of their organization as a type of masonic order. Mirala sees a similar connection between the masons and the Orange order. He argues that the Orange men, many of whom came from the lower levels of society, modeled their organization after the freemasons because the government refused to allow them to mobilize openly as a military organization. Many of the Orange order's early symbols and rituals, notably their parades, came from the masons. The high concentration of masonic lodges around Loughgall, where the Orange order first appeared, lends credence to this view.

In the final section of the book, Mirala explores how social, political, and ecclesiastical tensions combined to undermine freemasonry. Throughout the period of the study, the Grand Lodge and the local lodges of Ulster engaged in an ongoing power struggle concerning such things as the ownership of dues, the right to award the higher degrees of masonry, and attempts to limit membership to “respectable” men of property. This struggle culminated in a six-year split within the movement and the temporary creation of a second Grand Lodge in Ulster. Although the first Grand Lodge officially emerged victorious in 1813, masonry failed to recover the members it had lost. Even before the split, masonry had been losing members to the Orange order, which increasingly sought to distance itself from its masonic roots. At the same time, Irish Catholic bishops began encouraging Catholic laymen to leave the order by emphasizing the decades-old papal ban on freemasonry. By the 1820s, masonry's heyday was over.

As Mirala acknowledges, the book's main limitations stem from the incompleteness of its sources. Without an existing pool of local studies to draw from, Mirala arrives at his conclusions by making informed judgments using the materials at his disposal, while admitting that further research needs to be done. Despite this shortcoming, however, Mirala's work sheds light upon an understudied aspect of eighteenth-century Irish history and gives freemasonry its due as an influential part of Irish society. As Mirala himself suggests, his book is a starting point in the study of Irish freemasonry; he has opened up an intriguing ground for future study.