In the Smalcald Articles, (at the behest of his patron, Elector John Frederick of Saxony), Luther summarized what he regarded to be the most important teaching in Christianity, these Articles were prepared with the intention of being presented at the Schmalkaldic League's meeting in 1537 primarily to address concerns pertaining to the office and power of the Roman Catholic Pope. The League had been organized in 1531 as a union of various Lutheran territories and cities, to provide a united military and political front against Roman Catholic politicians and armies, led by Emperor Charles V. After some argument, the league ultimately determined not to adopt the articles Luther had written, instead adopting a treatise by Philipp Melanchthon. Although they were not adopted at the meeting of the Schmalkaldic League, they nonetheless gained wide acceptance and use and were eventually incorporated into the Book of Concord in 1580 as one of the Lutheran Confessions of the faith.