The Third Plenary Council of Baltimore
"While the ecclesiastical province of Baltimore comprised the whole territory of the American Republic, the provincial councils held in that city sufficed for the church government of the country. When, however, several ecclesiastical provinces had been formed, plenary council became a necessity for the fostering of common discipline. As a consequence, the Fathers of the Seventh Provincial Council of Baltimore requested the Holy See to sanction the holding of a plenary synod. The petition was granted and the pope appointed Archbishop Kenrick of Baltimore as Apostolic Delegate to convene and preside over the council." --Newadvent.org
THE MEANING OF A CATECHISM
A catechism is any book made up in question and answer form, no matter what it treats of. We have catechisms of history, of geography, etc. Our Catechism is a book in the same form treating of religion. It is a little compendium of the truths of our religion, of all we must believe and do. It contains, in the simplest form, all that a priest learns during his many years of study. The theology he learns is only a deeper and fuller explanation of the Catechism. A whole book might be written on almost every question. For example, might we not write a book on each of the first three questions—the World, God, and Man? There is consequently much meaning in the Catechism, which must be made known to us by explanation. You should therefore learn the Catechism by heart now, even when you do not fully understand it; because afterwards, when you read books on religion or hear sermons, all these questions and answers will come back to your mind. Sermons will help you to understand the questions, or the questions will help you to understand the sermons.