Pope St Pius X, whose feast we celebrate today, lived from 2 June 1835 to 20 August 1914, and was Pope from 1903 onwards. He was the first pope since Pope Pius V to be canonized. His life perhaps illustrates the problems associated with canonising popes!
On the one hand, Pope his tough stance against modernism, promotion of traditional devotional practices and Gregorian chant, promotion of Thomism, and catechism have won him many traditionalist fans. But his wreckovation of the traditional Roman Breviary, fiddling with the order of the sacraments, encouragement of frequent communion, and other liturgical innovations, arguably laid the ground work for the liturgical revolution of the twentieth century.
Pope Benedict XVI gave a General Audience on the saint in 2010:
"Today I would like to reflect on my Predecessor, St Pius X whose liturgical Memorial we shall be celebrating next Saturday and to underline certain features that may be useful to both Pastors and faithful also in our time.
Giuseppe Sarto, that was his name, was born into a peasant family in Riese, Treviso, in 1835. After studying at the Seminary in Padua he was ordained a priest when he was 23 years old. He was first curate in Tombolo, then parish priest at Salzano and then canon of the Cathedral of Treviso with the offices of episcopal chancellor and spiritual director of the Diocesan Seminary. In these years of rich and generous pastoral experience, the future Pontiff showed that deep love for Christ and for the Church, that humility and simplicity and great charity to the needy which characterized his entire life. In 1884 he was appointed Bishop of Mantua, and in 1893, Patriarch of Venice. On 4 August 1903, he was elected Pope, a ministry he hesitated to accept since he did not consider himself worthy of such a lofty office.
Pius X's Pontificate left an indelible mark on the Church's history and was distinguished by a considerable effort for reform that is summed up in his motto: Instaurare Omnia in Christo, "To renew all things in Christ". Indeed, his interventions involved various ecclesiastical contexts. From the outset he devoted himself to reorganizing the Roman Curia; he then began work on the Code of Canon Law which was promulgated by his Successor Benedict XV. He later promoted the revision of the studies and formation programme of future priests and founded various Regional Seminaries, equipped with good libraries and well-qualified teachers. Another important sector was that of the doctrinal formation of the People of God. Beginning in his years as parish priest, he himself had compiled a catechism and during his Episcopate in Mantua he worked to produce a single, if not universal catechism, at least in Italian. As an authentic Pastor he had understood that the situation in that period, due partly to the phenomenon of emigration, made necessary a catechism to which every member of the faithful might refer, independently of the place in which he lived and of his position. As Pontiff, he compiled a text of Christian doctrine for the Diocese of Rome that was later disseminated throughout Italy and the world. Because of its simple, clear, precise language and effective explanations, this "Pius X Catechism", as it was called, was a reliable guide to many in learning the truths of the faith.
Pius X paid considerable attention to the reform of the Liturgy and, in particular, of sacred music in order to lead the faithful to a life of more profound prayer and fuller participation in the Sacraments. In the Motu Proprio Tra le Sollecitudini (1903), the first year of his Pontificate, he said that the true Christian spirit has its first and indispensable source in active participation in the sacrosanct mysteries and in the public and solemn prayer of the Church (cf. AAS 36, 531). For this reason he recommended that the Sacraments be received often, encouraging the daily reception of Holy Communion and appropriately lowering the age when children receive their First Communion "to about seven", the age "when a child begins to reason" (cf. S. Congr. de Sacramentis, Decretum Quam Singulari: AAS 2  582).
Faithful to the task of strengthening his brethren in the faith, in confronting certain trends that were manifest in the theological context at the end of the 19th and the beginning of the 20th centuries, Pius X intervened decisively, condemning "Modernism" to protect the faithful from erroneous concepts and to foster a scientific examination of the Revelation consonant with the Tradition of the Church. On 7 May 1909, with his Apostolic Letter Vinea Electa, he founded the Pontifical Biblical Institute. The last months of his life were overshadowed by the impending war. His appeal to Catholics of the world, launched on 2 August 1914 to express the bitter pain of the present hour, was the anguished plea of a father who sees his children taking sides against each other. He died shortly afterwards, on 20 August, and the fame of his holiness immediately began to spread among the Christian people.
Dear brothers and sisters, St Pius X teaches all of us that at the root of our apostolic action in the various fields in which we work there must always be close personal union with Christ, to cultivate and to develop, day after day. This is the essence of all his teaching, of all his pastoral commitment. Only if we are in love with the Lord shall we be able to bring people to God and open them to his merciful love and thereby open the world to God's mercy. "