On a visit to Malta in 1838, Queen Adelaide expressed severe disappointment that the British colony did not possess a purpose-built Anglican place of worship. She determined to fund the building of one at her personal expense and within six years the grandiose neoclassical church of St Paul's, Valletta, was completed. This imposing structure occupied an ambiguous position in a colony where the British government was pledged to maintain Roman Catholicism. St Paul's was ostensibly intended for the existing Anglican population in Malta. However, the church was perceived by both evangelicals and Roman Catholics as a potential instrument of propagating Protestantism. In examining the basis for these perceptions, this article suggests that St Paul's was part of a larger effort, driven by high church clergy connected with the Society for Promoting Christian Knowledge (SPCK), to influence the Maltese towards greater sympathy with the Anglican tradition, while avoiding overt proselytizing. The concomitant establishment of the diocese of Gibraltar in 1842 was, it is argued, key to this enterprise. The analysis advanced here has important implications for our understanding of Anglicanism in an imperial context, the contribution of royal patronage to this process and the conflict between religious and governmental imperatives.