Father Pfefferkorn was born on July 31, 1726, on the feast day of Saint Ignatius, in Mannheim in the Archbishopric of Cologne. He had been a Jesuit since October 21, 1742. When he came to Guevavi in May 1761, he was 35 and, like Segesser, an astute observer.
Father Ignacio had given up Atíl on May 19, 1761, and had come to Guevavi to replace Father Gerstner. They were old acquaintances as they had shared the trip from Germany to New Spain, and arrived during the first days of 1757 to begin their ministries in the Pimería.
Word reached Father Pfefferkorn that Father Visitor General Ignacio Lizassoain had begun his dual-purpose visitation in April 1761. Because of the rainy season he did not arrive in Pimería Alta until November. He, like his predecessors, shunned Guevavi. He stopped at San Ignacio and the Padres of Pimería Alta came to him. Father Ignacio rode 65 miles to give his report on the mission’s progress and potential. By then he had been at Guevavi for nearly six months.
He presented for inspection the records of baptisms, marriages and burials. Beneath his most recent baptismal entry, the secretary of the visitation, Father Aguirre, recorded the Father Visitor General’s approval and his admonition that each and every entry be fully written out and signed separately. Some of his predecessors made multiple entries and signed only once. He presented a census of the villages in his charge. Of the eight mission cabaceras in Pimería Alta, Guevavi had the fewest neophytes. However, if you count the three visitas, Father Ignacio’s mission was not quite last.
For two years he buried nearly twice as many as he baptized. Always superstitious, the natives grew restless. At Tumacácori alone, during one 4-month period, the Padre recorded at least 20 admitted deaths. There may have been others that the Indians buried in the heathen manner.
When Felipe, popular native governor of Tumacácori died, the Papagos fled back to the desert. Only a few Pimas stayed at Calabazas and Tumacácori. Dutifully, Father Pfefferkorn reported the exodus to the Father Visitor General Lizassoain. The shadow of death hung over Guevavi’s villages and that was an ill omen.
The northern Pimería was in trouble. To save Soamca, Guevavi and Bac, something must be done to bring in and hold more Indians. At Horcasitas in early December 1761, after the Father Visitor General had noted the situation in his visitation, he discussed the situation with interim Governor Don Joseph Tienda de Cuervo. There a decision was reached, which later events would brand as a tragic error.
The Sobaípuris, long a buffer against the Apaches, still lived on the San Pedro beyond the effective control of the missionary. Why not move them into Soamca, Guevavi and Bac, thereby reinforcing those missions and consolidating frontier defenses. Father Keller, who would have opposed this, had been dead two years. Mendoza, who had advocated planting missions on the San Pedro, had died an agonizing death the year before, victim of a poisoned Seri arrow in the throat. Thus Cuervo wrote the order.
As Captain of the Vera Cruz Dragoons, Tienda de Cuervo had been on hand five years before to greet Father Pfefferkorn and his fellow Jesuits as they disembarked from the ship El Victorioso. Now unintentionally the same officer as Governor and Captain General of Sonora released the traditional “brake on the enemy” and brought the full fury of the Apache on Pfefferkorn’s frontier mission.
Captain Elías of Terrenate carried out the Governor’s order. At Tucson on March 19, 1762, he presided as a census of Sobaípuri immigrants was compiled. The total reached 250. Thirty Sobaípuri families were settled at Soamca. At Sonoita, Father Pfefferkorn began to baptize children brought from the rancherías on the San Pedro. “The good news” of the Sobaípuri reduction traveled to the Viceroy. Now the missions, Cuervo told his superior, could be better able to fend off Apache blows. The result was just the opposite.
Father Pfefferkorn’s most lasting contribution as a missionary has been his description of Sonora, published in Germany three decades after he left Guevavi. He did not write about himself and related few personal experiences. Not a word did he write of his two years at Guevavi. As an appendix to his chapter on native languages he included a glossary of Sonora place names. A modern scholar translates Guevavi as “big spring,” Tumacácori as “caliche bend,” and Tubac as “rotten.”
The purer air he sought, he did not find at Guevavi. No one knew more about the summer heat and disease-breeding marshes along the river near the mission than the current Father Visitor and amateur physician, Joseph Garrucho. In the spring of 1763, when Garrucho heard that Father Pfefferkorn lay very ill at Guevavi, he ordered the ailing Padre “removed from that climate” and brought to his own mission of Oposura for rest and recuperation.
Very soon after May 30, 1763, he either rode or was carried to Oposura. There he recovered. He was re-assigned to Cucurpe, where he continued to serve and amass material for his book. Garrucho said the German Padres did not prosper in tierra caliente. In Pfefferkorn’s place he sent a Spaniard, Custodio Ximeno.
After the expulsion, Fathers Pfefferkorn and Gerstner crossed to Spain from Vera Cruz, after November 10, 1768. They landed at Cádiz and the beautiful hospice there became a prison. In Spain they were put in monasteries under house arrest. Through the intercession of the Elector of Cologne, Father Pfefferkorn, who planned to write a book, was freed late in 1777.
 Pfefferkorn had been a Jesuit since October 21, 1742. Details of his trip to the New World with Gerstner, Middendorf, Och, and the rest are in his Sonora, pp. 2-9.
 Pfefferkorn, Sonora, p. 263. Father Gerstner last signed the Guevavi book of baptisms on May 26, 1761. Two days later Father Pfefferkorn began making entries. The entrega turning Guevavi over to Pfefferkorn is in WBS, 1744, ff. 381-84, and is translated in Appendix II below. Pfefferkorn had given up Atí on May 19, 1761. Entrega, ibid., ff. 377-80. Gerstner took over Sáric on June 14, 1761. Entrega, ibid., ff. 385-86.
 The five were Francisco Hlava, Miguel Gerstner, Ignacio Pfefferkorn, Bernardo Middendorf, and Joseph Och. For a delightful and perceptive description of their travels from Germany to the Pimería, see Treutlein, Travel Reports of Joseph Och, pp. 1-45.
 The record of Father Lizassoain’s visitation in the Guevavi books was dated November 19 at San Ignacio, which led Father Victor R. Stoner to conclude incorrectly that during Jesuit times Tumacácori was “often referred to as San Ygnacio de Tumacácori. . . . Even the Jesuit Visitor General Lizassoain (November 19. 1761) called it San Ignacio.” “The Spanish Missions of the Santa Cruz Valley,” unpublished Master’s thesis, University of Arizona, Tucson, 1937, p. 37.
 “Noticia de la Visita General del P. Ignacio Lizasoain Visitador General de las Missiones de esta Prov.a de Neuva España, q comenzó dia quarto de Abril de 1761 a.s y se concluyó á fines de Henero de 1763 con algunas notas y addiciones q. pueden server p.a el conocimiento de dhas Missiones, y Provincias de ellas”; WBS, 47. Tamarón y Romeral, Demostración, p. 391. The Bishop incorporated Father Lizassoain’s census figures in his own report, but adding widowers and widows as families he arrived at a total of 41 families for Guevavi, 50 for Calabazas, 38 for Sonoita, and 87 for Tumacácori. He also included the number of individuals at each of the four villages—111, 116, 91, and 199. Ibid., p. 304.
 Aguirre to Zevallos, Bacadéguachi, December 30, 1763; ibid.
 Pradeau, Expulsión, pp. 153, 196. Almada, Diccionario, p. 787.
 Tienda de Cuervo to the Marqués de Crujillas, San Miguel, April 5, 1762, certified copy, Mexico, June 16, 1762; AGI, Guad., 511.
 Beschreibung der Landsschaft Sonora samt andern merkwurdigen Nachrichten von den inneren Theilen Neu-Spaniens und Reise aus Amerika bis in Deutschland, 2 vols. (Koln am Rheine, 1794-95). Thanks to Dr. Treutlein, Father Pfefferkorn’s Sonora, cited above numerous times, has been available to English readers since 1949.
 Pfefferkorn admitted that he served as resident Padre at three missions, but he named only two—Atí and Cucurpe. Thus, on the basis of his Sonora alone, the identity of the third mission—Guevavi—was something of a mystery, even to Dr. Treutlein. Sonora, pp. 19-20.
 Garrucho to Reales, July 13, 1763.