Though the Lutheran teaching had been accepted, great care was taken not to shock the people by any violent change. Episcopal government of the Church was retained; most of the Catholic ritual in regard to the sacraments and the Mass was adopted in the new liturgy, and even in some cases the pictures and statues were not removed from the churches. But the revolution that Gustavus had most at heart was fully accomplished. The authority of the Pope had been overthrown, and in his place the king had been accepted as the head of the Swedish Church. Nor did the Lutheran bishops find themselves in the enjoyment of greater liberty and respect as a result of their treason to the Church. Gustavus warned them that they must not carry themselves like lords, and if they would attempt to wield the sword he would know how to deal with them in a summary manner. Resenting such dictation and tyranny they began to attack Gustavus in their sermons and to organise plots for the overthrow of his government. The conspiracy was discovered (1540). Olaf and Laurence Peterson, the two prominent leaders of the reforming party, were condemned to death, but were reprieved on the payment of a large fine. Laurence was, however, removed from his position as Archbishop of Upsala. In the Diet of Vesteras in 1544 the crown of Sweden was declared to be hereditary, and was vested in the family and heirs of Gustavus. Thus the well-considered policy of Gustavus was crowned with success. By means of the Lutheran revolt he had changed the whole constitution of the country, had made himself absolute master of Sweden, and had secured the succession to the throne for his own family.
But he had not broken the power of his opponents so completely as to bring peace to his country, nor, if credence be given to the proclamations in which he bewailed the increase of evil under the plea of evangelical freedom, did the reformed religion tend to the elevation of public morals. On his death in 1560 he was succeeded by his son Erik XIV. (1560-9). Hardly had the new king been proclaimed than the principle of private judgment introduced by the reformers began to produce its natural results. Calvinism, which was so opposed to Lutheranism both in doctrine and in church government, found its way into Sweden, and attracted the favourable notice of the king.
Regardless for the time being of the Catholic Church, which to all appearances was dead in Sweden, the two parties, Lutherans and Calvinists, struggled for supremacy. Erik was won over to the side of the Calvinists, and measures were taken to overcome the Lutherans by force, but the king had neither the capacity nor the energy of his father. The plan miscarried; the Calvinists were defeated (1568), and Erik was deposed and imprisoned.
His younger brother John succeeded to the throne under the title John III. He was a man of considerable ability, and was by no means satisfied with the new religion. His marriage with Catharine, sister of Sigismund, King of Poland, herself a devoted Catholic, who stipulated for liberty to practice her religion, helped to make him more favourable to a Catholic revival. He set himself to study the Scriptures and writings of the Holy Fathers under the guidance of Catharine's chaplains, and convinced himself that he should return to the Catholic Church and endeavour to rescue his country from the condition of heresy into which it had fallen. He allowed the monks and nuns who were still in Sweden to form communities again, and endeavoured to win over the clergy by a series of ordinances couched in a Catholic tone which he issued for their guidance. In 1571 he induced the Archbishop of Upsala to publish a number of regulations known as the /Agenda/, which both in ritual and doctrine indicated a return to Rome, and he employed some Jesuit missionaries to explain the misrepresentations of Catholic doctrine indulged in by the Lutheran and Calvinist leaders. His greatest difficulty in bringing about a reunion was the presence of Lutheran bishops, but fortunately for him many of them were old men whose places were soon vacant by death, to whose Sees he appointed those upon whom he could rely for support. When he thought the time was ripe he summoned a National Synod in 1574, where he delivered an address deploring the sad condition to which religious dissensions had reduced the country. He pointed out that such a state of affairs had been brought about by the Reformation and could be remedied only by a return to the Church. The address received from the clergy a much more favourable reception than he had anticipated. As the Archbishopric of Upsala was vacant, he secured the election of an archbishop, who have his adhesion to seventeen articles of faith wholly satisfactory to Catholics, and who allowed himself to be consecrated according to the Catholic ritual. He promised also to use his influence to secure the adhesion of the other bishops. In 1576 the king issued a new liturgy, /The Red Book of Sweden/, which was adopted by the Diet in 1577, and accepted by a large body of the clergy. Its principal was the king's brother, Karl, Duke of Suthermanland, who for political reasons had constituted himself head of the Lutheran party, and who refused to agree with the Roman tendencies of the king on the ground that they were opposed to the last wishes of Gustavus and to the laws of Sweden. A disputation was arranged to take place at Upsala, where the Belgian Jesuit, Laurence Nicolai, vindicated triumphantly against his Lutheran opponents the Catholic teaching on the Church and the Mass. Copies of the celebrated catechism of the Blessed Peter Canisius were circulated throughout Sweden, and made an excellent impression on the people.
