This thesis is a prosopographical study of the participation of Catholic peers in the parliaments
of James I, which attempts to reintegrate the history of English Catholicism within a wider
political context. It wrestles with the problems of definition, takes a broad view of who might
be counted as having Catholic allegiances, and then seeks to investigate how those peers
performed their parliamentary duties. This study thus hopefully contributes findings to two
broad fields of research that have hitherto been treated at arm’s length: the history of
parliament, and the history of post Reformation English Catholicism. In concentrating on the
reign of James I, it also forms part of valuable work that has been done in recent years to
rehabilitate the reputation of that monarch, and pay due attention to parliamentary activity in
this period without undue reference back to Elizabeth I, or forward to problems under Charles
I. The thesis draws on the wide range of printed material that has been made available on
early modern Parliaments in recent years, from the journals of both houses to printed diaries,
and latterly, the invaluable biographical research of the History of Parliament Trust and the
Nun’s Project. Taking up the baton of revisionist historians in both camps, this thesis asks
fundamental questions about the work of Catholic peers in the House of Lords, their
attendance, committee work, use of proxies, and possible influence in elections for members
of the House of Commons. It also enlarges on the work of revisionists working on Catholicism
with the push to see English Catholics as better integrated than images of a persecuted,
isolated minority might suggest. English Catholics under James I played a prominent part at
court, in government, and at Westminster, even though this period also witnessed scares
regarding the gunpowder plot and the assassination of Henry IV of France. The thesis
demonstrates that English Catholic peers played a full part in the work of Parliament during
the reign of James I, a role that needs to be better understood if we are to form a full
understanding of the work of that institution. English Catholic peers played their part in both
national and local politics, and in the work of both houses of Parliament; they were very much
part of the Jacobean political establishment.