This volume reproduces, with an extended introduction, a series of newsletters and position papers composed by Catholic writers in England, France, Flanders and Rome during the early 1620s. The principal topic of their correspondence was the dynastic foreign policy of the Stuart court and the intention of King James I to guarantee the succession of the senior line of the House of Stuart. As these letters commence, the Stuart court was determined to secure a marital match with the Spanish branch of the House of Austria. When this project failed in the summer of 1624, the Stuarts' dynastic diplomacy focused on an Anglo-French treaty instead. However, the political difficulties caused by this attempt to secure a cross-confessional dynastic union with a major European Catholic power threatened the internal political stability of the Stuart State and directly contributed to the unsettled nature of the Caroline polity after 1625.