The Church of France was ravaged by the heresy of the Albigenses who, not satisfied with teaching false doctrine, pillaged the churches and massacred the priests. In 1215, Innocent III saw in a dream the tottering walls of St. John Lateran, held up by the powerful shoulders of a friar. This friar was St. Dominic whose preaching defended Catholic doctrine against the new heresies (Epistle). Before his birth, his mother had in a vision her child in the shape of a little dog holding in its mouth a torch which was to set the world on fire.
Called Dominic, because his parents attributed his birth to the prayers of the holy Benedictine abbot Dominic of Silos, he truly belonged to the Lord, as his name suggests. Born in Spain, of the noble family Gusman, he distinguished himself by his purity as is signified by the lily he holds (Alleluia) and his white habit.
Having witnessed the many evils caused by the heretics in the south of France, he founded to oppose them the Order of the Friars Preachers (Communion), whom he armed with the shield of truth to teach doctrine and the sword of the word to preach it.
The Dominicans number many saints of both sexes who, like their founder, ardently studied the Word of God in the Gospel, which as St. Dominic says is the book of truth and "the book of charity".
[The Order of the Friars Preachers has given to the Church 4 popes: Blessed Innocent V St. Pius V, Benedict XI, Benedict XIII; numerous cardinals, bishops, doctors, preachers and illustrious writers. It numbers 11 saints and 4 women saints, 268 beatified men and 24 beatifled women, of whom 300 martyrs. The census of the Order in 1935 showed that there were 6000 Friars. The Dominican nuns in the Second Order and in the Third Order amount to 40,000.]
This saint loved our Lady in a special manner and preached the devotion to the Rosary. He died on August 6, 1221.
Os justi meditabitur sapientiam, et lingua ejus loquetur judicium; lex Dei ejus in corde ipsius. * Noli aemulari in malignantibus: neque zelaveris facientes iniquitatem.
The mouth of the just shall meditate wisdom, and his tongue shall speak judgement: the law of his God is in his heart. * Be not emulous of evildoers: nor envy them that work iniquity.
(Psalm 36:30-31,1 from the Introit of Mass)
Deus, qui Ecclesiam tuam beati Dominici Confessoris tui illuminare dignatus es meritis et doctrinis: concede; ut ejus intercessione temporalibus non destituatur auxiliis, et spiritualibus semper proficiat incrementis.
O God who, by the merit and teaching of blessed Dominic, Thy confessor, hast been pleased to enlighten Thy Church: grant that through his prayers, she may not be deprived of temporal help, and may continually advance in spiritual growth.
From the Catholic Encyclopaedia: http://www.newadvent.org/cathen/05106a.htm