The council itself left several tasks unfinished and handed them to the papacy, which produced in the following decades a catechism, a revised breviary and a revised missal. The result was a degree of uniformity in Catholic worship and teaching that had never existed before: from the late sixteenth century a Catholic could hear substantially the same mass in the same language in Lima, Goa and Cracow. That uniformity, rather than any single decree, is the practical legacy of the council.
It held for four centuries. The word Tridentine, from the Latin name of the city, still marks that liturgy and that profession of faith, and the reason the Second Vatican Council registered as such a shock in the 1960s is that it altered arrangements which several generations had experienced as simply what the church was.
Historians have revised the older picture of Trent as a purely defensive counter-reformation. Movements of Catholic reform, new orders, reforming bishops and a renewed devotional literature were under way before Luther and continued alongside the council, and the term Catholic Reformation is now used at least as often as Counter-Reformation. Both readings capture something: much of what Trent enacted answers Protestant criticism directly, and much of it answers complaints that Catholics had been making about their own church for a century.