Over the course of English parliamentary history there were a number of Acts of Uniformity. All had the basic object of establishing some sort of religious orthodoxy within the Church of England.
The Act of Uniformity 1548 (2 & 3 Edw. 6. c. 1), also called Act of Equality, which established the Book of Common Prayer as the only legal form of worship
The Act of Uniformity 1552 (5 & 6 Edw. 6. c. 1) required the use of the Book of Common Prayer of 1552