I remember once flipping through a book in a bookstore that contained all the saints observed in the Episcopal Church. I was astonished to see that St. Ignatius was one of them.
Maybe it was St. Ignatius of Antioch, but if it was the St. Ignatius whom Holy Mother Church honored today, there may be an explanation.
Despite the Anglican Schism, the early generations of British Protestants in the 16th and 17th centuries still read the great spiritual works of the Saints. The
Spiritual Exercises of St. Ignatius being one of them. This was because the Anglican polemicists focused too much on theological and political disputes (against the Church and amongst themselves) and the learned amongst them were too busy butchering up the Holy Scriptures and the Sarum Missal (which they degraded and deformed into the Book of Common Prayer), for them to develop some form of spirituality. Therefore, a great need for spiritually edifying literature existed amongst the early Anglican schismatics, and the "high church" Anglicans tended to read Catholic works.
An example is the 17th century Anglican Welsh poet and writer, Henry Vaughn, who read the Saints and praised their example, and even wrote a biography of St. Paulinus of Nola. During the time of Cromwell's tyranny, he especially became radicalized to the point of even writing like a Catholic, though he never embraced the faith.
It is a historical curiosity, which remains memorialized in some circles of "High Church" Anglicans and Episcopalians, though they themselves may not know the etiology thereof.
Why would any religious group celebrate as a saint someone dedicated to their destruction? It would be like us celebrating the feast of St. Martin Luther.
Ask John Paul II, :D