Due to the upheavals of the Thirty Years’ War (1618–1648), Kircher spent his early manhood as a wandering scholar. After several years at Fulda, he completed his preliminary studies at the college in Mainz. From there, having successfully applied for admission to the Jesuit order, he proceeded to Paderborn to begin his novitiate. In 1620, Kircher took his first vows and began a course in natural philosophy, which was interrupted the following year when Duke Christian of Brunswick’s Protestant army seized Paderborn. The entire Jesuit college fled, and Kircher found his way to the college at Cologne. After completing his course of philosophy, he was sent to Koblenz to teach Greek while he finished his remaining studies. From Koblenz, Kircher was transferred to the College of Heiligenstadt in Saxony, in turn followed by a stint of service in the household of the archbishop of Mainz. In 1628, he was ordained as a priest and began his tertianship (a period of withdrawal and spiritual contemplation following ordination) in Speyer. After his request to serve as a missionary in China was rejected, Kircher was appointed professor in moral philosophy, mathematics, and the sacred languages of Hebrew and Syriac at the Jesuit college in Würzburg. Once again, warfare intervened, this time forcing Kircher to abandon Germany altogether. In 1631, Gustavus Adolphus seized control of Würzburg, and Kircher escaped to Paris, where he was dispatched to Avignon to resume teaching. While at Avignon, Kircher became acquainted with the French savant, aristocrat, antiquarian, and patron of scholarship, Nicolas-Claude Fabri de Peiresc, whose personal collection of manuscripts and antiquities led Kircher to his seminal research into Coptic and the Eqgyptian hieroglyphs.

In 1633, Kircher was ordered to Vienna to serve as imperial mathematician at the Habsburg court, a title formerly held by Johannes Kepler. He set off by sea to assume his new post, but never made it to Vienna. While Kircher was being robbed, deserted, and tossed about by violent storms in the course of his journey across the Mediterranean (Kircher’s autobiography describes numerous misadventures and near-death experiences), Peiresc intervened with the powers in Rome to have Kircher’s assignment changed. Following his unscheduled landing at Civitàvecchia on the Italian coast, Kircher hiked the short distance to the Holy City, intending to pay his respects before continuing on to Vienna, only to learn that he was now expected there.

One year after the Holy Office condemned Galileo for upholding the Copernican hypothesis, Kircher was appointed professor of mathematics at the Collegio Romano.

Kircher’s subsequent influence on contemporary scientists and on developments in medicine, microscopy, earth sciences, optics, acoustics, mechanical engineering, chemistry, archaeology, and Egyptology was considerable. For example, in the early numbers of the Royal Society’s journal, Philosophical Transactions, there are over 100 references to the writings, discoveries, and views of Kircher and his fellow Jesuit scientists, including extensive book reviews of such Kircher titles as Mundus subterraneus (Amsterdam, 1665) and China monumentis qua sacris qua profanis (Amsterdam, 1667).

Reilly describes Kircher (along with Henry Oldenburg, Marin Mersenne, and Nicolas-Claude Fabri de Peiresc) as a great pioneer of international scientific intercommunication:

Kircher was above all an “intelligencer”, in the Baconian sense, a “philosophical merchant”, a provider of data, a stimulator of thought. He answered the needs of men’s curiosity, bringing together the unusual, the unknown, the marvellous from his world-wide network of contacts. In his books, he collected this diverse information, adding his own speculations, enriching them with what he had culled from the wisdom of the past and from contemporary writers.

With the many beautifully-designed books he published, the letters he wrote, the inventions he made, and the collections he organized, Kircher inspired virtuosi around the globe:

But Kircher was not only a provider of encyclopaedic information, a gatherer of data. He was also a stimulating and invigorating personality, and it was his ability to encourage others, to trigger the development of far-reaching ideas in their minds, that may really have been his most worthwhile contribution to the world of science. When the noble Scottish prisoner, Sir Robert Moray, was lifted from his depression and fired with an interest in physical science by reading Kircher’s Magnes back in 1644, an important step was taken. Through Moray’s activities in helping to found the Royal Society of London, this step can be said to have been of the greatest significance to science. Others reading Kircher’s books received inspirations valuable to their own progress. Even when what they read in Kircher appeared to them to be at fault, their efforts to correct his views acted as a stimulus to further discovery in science. Thus Boyle drew on Kircher’s writings on colour, Nicholas Steno on his geology, others on his acoustics, optics and the many other topics he ranged over in his discursive and vast tomes. But it was possibly through his correspondence and his personal contacts that he achieved most. The scale of his correspondence was vast and touched on a host of scientific topics, from astronomy to logic. His letters encouraged others to continue with their work, to search for new ideas, develop new approaches. Those who came to see him in his study and museum at the Roman College, who brought him queries such as those Southwell brought from the Fellows of the Royal Society of London, were also encouraged and directed in the same way. His inspiration was effective, for many of his acquaintances, his friends and collaborators, became themselves prolific writers and enthusiastic scientists. It does not detract from his achievement that many of the men he encouraged and helped were minor figures in science and scarcely register on the scale of what we today consider to be the history of the Scientific Revolution. We tend, because of obvious limitations of time and energy, to concentrate on the major figures and the more outstanding events in that history, but if space allowed we would be obliged to grant an important part also to the “minor” figures, the teachers, professors, the men of one idea, of one small forward step, all of whom contributed something more or less essential to the development of modern science. It was this substratum, the background crowd and supporting cast, who above all were stimulated by Kircher and his writings. Without the supporting cast, where would the stars be?