Co-cathedral is the name given to a 
cathedral church which shares the honour of being a bishop's seat with another cathedral. Instances of this occurred in 
England before the 
Protestant Reformation in the dioceses of 
Bath and 
Wells, and of 
Coventry and 
Lichfield, hence the names of these dioceses. In 
Ireland, an example occurs at 
Dublin, where 
Christ Church and 
St. Patrick's are jointly the cathedral churches of that diocese. In 
France the bishop of 
Couserans[?] (a see suppressed at the Revolution) had two co-cathedral churches at 
St Lizier[?], and the bishop of 
Sisteron[?] (a see also suppressed) had a second throne in the church of 
Forcalquier[?] which is still called 
La Con-cathédrale. Other instances might be named. 
In the case of York the collegiate churches[?] of Beverley, Ripon[?] and Southwell[?] were almost in the same position, but although the archbishop had a 
stall in each he had no diocesan cathedra in them, and the chapters were not united with that of the metropolitan church in the direct government of the diocese, or the election of the archbishop, nor had they those other rights which were held to denote the cathedral character of a church.
 
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