John III of Sweden moves towards embracing the Catholic faith. A
devoted theologian, John believed it was possible to synthesise
Lutheranism and Catholicism, and introduced to Swedish church
practice a liturgy of his own devising, 'the Red Book', which
reinstated some of the features that had been swept away in the
Reformation.
Citation:
Editors. "John III of Sweden unofficially becomes Catholic".
The Literary Encyclopedia. First published 01 February 2011
[http://www.litencyc.com/php/stopics.php?rec=true&UID=15238, accessed 19 May 2013.]