The Knights of the Cross with the Red Star (Křižovnický řád rytířů s červenou hvězdou; Kreuzherren mit dem Roten Stern; Ordo Militaris Crucigerorum cum Rubea Stella) is a religious order originating from Bohemia, devoted mainly to offering medical care. Throughout its history it was accustomed to the use of arms, a custom which was confirmed in 1292 by an ambassador of Pope Nicholas IV. The grand master is still invested with a sword at his induction into office, and the congregation has been recognized as a military order by Popes Clement X and Innocent XII, as well as by several Holy Roman Emperors.
The order as a distinct entity in the 13th century time can trace its origin to a Franciscan-based fraternity attached to a hospital at Prague under a community of Clarisses, established by Princess Agnes, in 1233, making it the only male order founded by a woman and the only Czech-founded order. In 1235 the hospital was richly endowed by the queen with property formerly belonging to the German order, a gift confirmed by Pope Gregory IX (18 May, 1236), who stipulated that the revenues should be divided with the Clarisse monastery. After three years, during which the head of the congregation had gone to Rome as the accredited representative of abbess Agnes, and the congregation had been formally constituted an order under the Rule of St. Augustine by Gregory XI (1238), the abbess resigned all jurisdiction over the hospital and its possessions into the hands of the Holy See the next year. Twelve days later the pope formally assigned these to the recently confirmed Knights of the Cross with the Red Star, who were to hold them forever in fief to the Holy See, on condition of the yearly payment of a nominal sum.
The order, which by 1253 had extensive possessions in Bohemia, soon spread to neighbouring lands. The Wrocław house in particular was the centre of many other foundations. It is Bohemia, in an especial manner, to which the knights have rendered incalculable services. Their success in hospital work is evidenced by the rapidity with which their houses multiplied, and the frequent testimony borne to it in documents of kings and emperors. Within two decades after their foundation the care of souls had become as important as their hospital work, so quickly had the majority of lay brothers been replaced by priests. Numberless churches were entrusted to them in all parts of Bohemia, particularly the West, where they formed a bulwark of the Faith during the ravages of heresy in that region; the Taborites killed the pastor of St. Stephen's at Prague, and the Hussites destroyed the mother-house and brought the order almost to the point of dissolution, but it recovered sufficiently to the offer strenuous resistance to the advance of the Reformed teachings. In the war with Sweden the members of the order justified their claim to the title of knights during the siege of Cheb, fighting side by side with the townspeople, and sharing with them their last crust. Their hospital at Prague was also the first refuge of other orders who came to work for souls in Bohemia, among others the Jesuits (1555) and Capuchins (1599). For almost a hundred and fifty years the archbishops of Prague held the post of grand master and were supported almost entirely by the revenues of the order. Only on the restoration of the possessions of the archdiocese at the end of the seventeenth century was the grand master again elected from among the members, and a general reform instituted. George Ignatius Paspichal (1694-99), the first grand master under the new regime, showed great zeal for the restoration of the primitive ideals, especially that of charity. Even to the present day the Prague monastery supports twelve pensioners and distributes the so-called "hospital portion" to forty poor.
Many knights have won enviable reputations in the world of learning, among others Mikuláš Kozař of Kozařov (died 1592), a celebrated mathematician and astronomer; Jan František Beckovský (1658 - 1725), who established at Prague an herbarium which is still in existence.
At the present time, besides the mother-house at Prague, there are about 26 incorporated parishes, and 85 professed members, several of whom are engaged in gymnasia and the University of Prague. There are benefices at Hadrisk, Vienna, where the order has been established since the thirteenth century, Cheb, Most and other towns especially in western Bohemia.
Castle of Dobřichovice near Prague was in the past serving as summer residence of the grand master of Knights of the Cross with the Red Star.
In 1990, the Order headquarters moved into the church next to Prague's Charles Bridge, after over 40 years of suppression during the communist era.