Another old Lutheran hymn used to include a verse along the lines of "protect us from Pope and Turk."
You remember correctly -- Googling "Pope and Turk" gives a children's song (!) "Lord, keep us in Thy Word and Work." by Martin Luther, 1483-1546. Text From: THE HYMNS OF MARTIN LUTHER. (New York: Charles Scribner's Sons, 1883), p. 67
1. Lord, keep us in thy word and work,
Restrain the murderous Pope and Turk,
Who fain would tear from off thy throne
Christ Jesus, thy beloved Son.
2. Lord Jesus Christ, thy power make known,
For thou art Lord of lords alone.
Shield thy poor Christendom, that we
May evermore sing praise to thee.
3. God, Holy Ghost, our joy thou art,
Give to thy flock on earth one heart.
Stand by us in our latest need,
And us from death to glory lead.
Hymn XXXIII from "The Hymns of Martin Luther". Author: Martin Luther. Titled: "Erhalt uns, Herr, bei deinem Wort."
Melody: 1543. Harmony: William Sterndale Bennett, 1865
1st Published in: Klug's "Gesangbuch", 1543. "A children's song, to be sung against the two arch-enemies of Christ and his holy Church, the Pope and the Turks."
From the Catholic side...
The appearance of Halley's comet, in 1456, just as the Turks had become masters of Constantinople, and threatened an advance into Europe, was regarded by Christendom with a superstitious dread, and to the Ave Maria was added the prayer: "Lord save us from the devil, the Turk, and the comet." Chambers Encyclopaedia (1877)
From the Anglican liturgy (1565)
The Turk goeth about to set up, to extol, and to magnify that wicked monster and dammed soul Mohumet above thy dearly beloved Son Jesus Christ, whom we in heart believe, and with mouth confess, to be our only Saviour and redeemer.
Moslems and the History of Anglican Liturgy
http://216.239.57.104/search?q=cache:BNhOQ0b_ST0J:www.compusmart.ab.ca/fhenders/pdf/moslems_anglican.pdf+litany+saints++turk&hl=en