 The original statutes , based heavily on those of the Order of the Garter , prescribed that any vacancy should be filled by the Sovereign upon the nomination of the members . Each Knight was to propose nine candidates , of whom three had to have the rank of Earl or higher , three the rank of Baron or higher , and three the rank of Knight or higher , and a vote taken . In practice this system was never used ; the Grand Master would nominate a Peer , the Sovereign would usually assent , and a chapter meeting held at which the knights " elected " the new member . The Order of St Patrick differed from its English and Scottish counterparts , the Orders of the Garter and the Thistle , in only ever appointing peers and princes . Women were never admitted to the Order of St Patrick ; they were not eligible to become members of the other two orders until 1987 . The only woman to be part of the Order was Queen Victoria , in her capacity as Sovereign of the Order . Although it was associated with the established Church of Ireland until 1871 , several Roman Catholics were appointed to the order throughout its history . 
