... is the feast of our Lady Auxilium Christianorum, commemorating the return of the Holy Father Pius VII from Napoleonic captivity to Rome.
This festival used to be on the unified Calendar for the Dioceses of England and Wales (duplex maius), while there was such a thing. When separate calendars and propers were granted for each individual diocese, it disappeared except in Menevia and Shrewsbury. In the latter of these, it remained as a double of the first class with an octave because our Lady Help of Christians was the titular of the cathedral and patron of the diocese ... which in those days penetrated deep into Wales (the first Bishop built his Episcopium at Pantasaph and is buried there).
In Menevia, where our Lady under this title was Patron of the diocese, she retained this title with this rank. (In Cardiff ... I knew you were wondering ... May 24 was the Dedication Day of the Cathedral and so our Lady doesn't get a look-in.)
Is there something going on here ... I mean, was there perhaps in those western regions a Bishop or a Vicar Apostolic who, out of a great devotion to our Lady Help Of Christians, or to the Temporal Power of the Papacy, or to both, spread this Patronage and this festival far and wide? Baines, possibly? or Ullathorne?
And then, of ourse, there is Australia, where our Lady Help of Christians is Patron (Solemnity in the Ordinariate of the Southern Cross). And ... BTW ... the Mass in the Ordinariate Missal is a translation of the Latin Mass in the Appendix pro aliquibus locis of the old Authentic Roman Missal. Another indication of the authentic liturgical spirit of the Ordinariates. Hands off, Roche!
Incidentally ... is our blessed Lady still Patron of New Zealand sub hoc titulo?
Purely pragmatically: our Lady is eleousa on Byzantine calendars, and Misericordiae in her propers as Auxilium Christianorum. But those who this year felt the loss of her last Sunday ... well, there is today. And those who this year feel the loss of Cardinal Mercier's feast of our Lady Mediatrix of All Graces ... well, there is today! The Supreme Ordo Compiler hasn't left you comfortless ...
Does anybody know anything about the Brandimarte who, according to Google links, wrote the delightfully, exuberantly, Baroque Office Hymns for this feast? The Sapphic metre does fit this sort of thing rather well, doesn't it?