The Catholic population was growing so fast that the Willesden clergy found it difficult to cope with the demand at the Green, and in 1903 Archbishop (later Cardinal) Bourne decided that a separate parish was necessary.
He entrusted the Willesden Green Mission (a vague area, extending to Blackbird Hill at least) to the Diocesan Missionaries of Our Lady of Compassion (now the Catholic Missionary Society). They had been founded in 1902, shortly before Cardinal Vaughan’s death, specifically to “spread the Faith among non-Catholics”.
Their first Superior was Fr. Charles Rose Chase, a colourful ex-army officer who habitually wore a top-hat. Fr. Chase had four priests with him initially, who all served in Willesden Green and of whom two, Dr. Herbert Vaughan and Dr. John Arendzen were to have a long association with this parish. Dr. Vaughan was a nephew of the Cardinal; Dr. Arendzen was one of four priest brothers of whom the youngest, Alphonse, was to serve in the parish from 1923 to 1929.
The Archbishop wished the Missionaries to be parish based; the Missionaries themselves, after short periods in various London parishes and now at Warwick Square, had asked to work in fresh territory. They were soon established, nearly simultaneously, at Willesden Green and at Saffron Walden.