Roman Catholic Archdiocese of Baltimore

The Metropolitan Archdiocese of Baltimore is the premier see of the Roman Catholic Church in the United States. The archdiocese comprises the City of Baltimore and 9 of Maryland's 23 counties in the central and western portions of the state: Allegany, Anne Arundel, Baltimore, Carroll, Frederick, Garrett, Harford, Howard, and Washington. The archdiocese is the metropolitan see of the larger regional Ecclesiastical Province of Baltimore. The Archdiocese of Washington was originally part of the Archdiocese of Baltimore.

The Archdiocese of Baltimore is the oldest diocese in the United States whose see city was entirely within the nation's boundaries when the United States declared its independence in 1776. The Holy See granted the Archbishop of Baltimore the right of precedence in the nation at liturgies, meetings, and Plenary Councils on August 15, 1859. Although the Archdiocese of Baltimore does not enjoy "primatial" status, it is the premier episcopal see of the Roman Catholic Church in the United States of America, as "prerogative of place".

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