William Lilly: A historical overview

On a September morning in 1666, William Lilly sat down to cast a horary chart for a client. The question: “What will become of London?” The answer, as he later wrote, was fire. Within days, the Great Fire consumed the city. William Lilly (1602–1681) was the most influential English astrologer of the 17th century, whose work Christian Astrology (1647) remains the foundational textbook of horary astrology. His predictions shaped public events, his almanacs outsold all rivals, and his methods are still used by practitioners today.

Definition: Who Was William Lilly?

William Lilly was an English astrologer, almanac writer, and occult author active during the turbulent decades of the English Civil War, the Commonwealth, and the Restoration. He specialized in horary astrology (answering specific questions by casting a chart for the moment the question was asked) and in mundane astrology (predicting national events). His book Christian Astrology (1647) was the first major English-language astrological textbook, and it remains in print today. He also published annual almanacs under the pseudonym “Merlinus Anglicus” that sold tens of thousands of copies each year.

Lilly was not a university scholar. He was a self-taught practitioner who rose from modest beginnings to become the most consulted astrologer in London. His clients included members of Parliament, royalists, and ordinary citizens seeking answers about health, marriage, lost property, and the fate of the nation.

From Diseworth to London: The Making of an Astrologer

Lilly was born on May 1, 1602, in Diseworth, Leicestershire. His father was a yeoman farmer. At age 18, he moved to London as a servant to a wealthy merchant. There he gained access to books and began studying astrology in secret, reading works by Ptolemy, Guido Bonatti, and the Elizabethan astrologer John Dee.

In 1632, Lilly met the astrologer John Evans, who taught him the practical art of horary. Evans was a Welsh clergyman and astrologer who had fallen on hard times. Lilly paid him for lessons and soon surpassed his teacher. By 1644, Lilly had published his first almanac, Merlinus Anglicus Junior, under a pseudonym. It was an instant success.

The English Civil War (1642–1651) created a massive demand for political predictions. Lilly’s almanacs openly supported the Parliamentarian cause. He predicted the execution of Archbishop Laud in 1645 and the defeat of King Charles I. In 1647, he published Christian Astrology, a massive three-part work that explained the principles of horary, electional, and mundane astrology. It was the first such book written in English rather than Latin, making astrology accessible to a wider audience.

The Trial That Nearly Broke Him

Lilly’s success made him enemies. In 1651, he was arrested and tried for witchcraft and treason. The charge stemmed from a pamphlet he had written that allegedly predicted the death of the king. At his trial, Lilly defended himself by arguing that astrology was a natural science, not magic. He was acquitted, but the experience left him cautious.

That caution did not last. In 1666, after the Great Fire of London, Lilly was called before a parliamentary committee to explain a pamphlet he had published years earlier that seemed to predict the fire. He claimed the prediction was misunderstood: he had only warned of “fire and sword” in general. The committee accepted his explanation, but public suspicion lingered.

What Lilly Actually Practiced

Lilly’s astrology was relentlessly practical. He cast charts for lost objects, stolen goods, missing persons, illness, pregnancy, marriage, and business decisions. His method, laid out in Christian Astrology, is systematic: the astrologer notes the exact time and place the question is asked, erects a chart for that moment, and interprets the positions of the planets and the houses according to a strict set of rules.

For Lilly, the central concept in horary was the significator: the planet that rules the house corresponding to the question. If you asked about a lost ring, the second house (money and possessions) and its ruler would be examined. If the significator was well-aspected, the ring would be found. If afflicted, it was gone.

Lilly also practiced electional astrology: choosing the most favorable time to begin an undertaking. He cast charts for the launch of ships, the signing of treaties, and even the coronation of Charles II (though he was a Parliamentarian, he adapted after the Restoration).

The Symbolism in Lilly’s Charts

Lilly did not invent new symbols. He inherited the medieval astrological tradition: the seven planets, the twelve signs, the twelve houses, and the aspects (conjunction, sextile, square, trine, opposition). What he added was a rigorous method of judgment.

In a horary chart, each house has a meaning. The first house is the querent (the person asking). The seventh house is the partner or the opponent. The tenth house is career and reputation. Lilly’s genius was in the details: he knew that a planet in its own sign or exaltation was strong, while a planet in detriment or fall was weak. He knew that the Moon carried the question forward, and that the fixed stars could tip a judgment.

For practitioners today, Lilly’s charts are still read using his rules. The symbolism is not abstract. It is a language of relationships: this planet aspects that planet, this house contains that sign, this degree is sensitive. The chart is a map of a moment, and Lilly taught how to read it.

How Lilly’s Work Is Used Today

Christian Astrology has never gone out of print. Modern horary astrologers treat it as the definitive text. The book is divided into three parts: the first explains the basics of astrology (signs, planets, houses, aspects), the second gives rules for answering specific questions (over 100 example charts), and the third covers mundane astrology and eclipses.

Lilly’s example charts are still studied. He recorded the date, time, and location of each chart, along with the question and his judgment. These are not theoretical exercises. They are real consultations, and they show his method in action. For example, one chart asks whether a stolen horse will be recovered. Lilly judged that it would, because the significator of the thief was in the twelfth house (enemies) but applying to a favorable aspect. The horse was found three days later.

Modern software can replicate Lilly’s calculations, but the interpretive skill remains human. Many astrologers still use his aphorisms, such as “The Moon separating from a planet shows the matter is past” or “A planet in the eighth house often signifies death or debt.”

Lilly and His Contemporaries

Lilly was not the only astrologer of his era, but he was the most visible. John Dee (1527–1608) had preceded him, but Dee’s astrology was mixed with alchemy and angelic communication. Lilly kept his practice clean: no spirits, no rituals, just calculation and judgment.

His rival was John Gadbury (1627–1704), a younger astrologer who initially admired Lilly but later turned against him. Gadbury was a royalist and a Catholic, and the two engaged in bitter pamphlet wars. Gadbury accused Lilly of being a fraud and a sorcerer. Lilly responded by calling Gadbury an ignorant plagiarist. The feud lasted decades.

Another contemporary was Nicholas Culpeper (1616–1654), the herbalist and astrologer-physician. Culpeper used astrology to prescribe medical treatments, a tradition Lilly respected but did not practice. Lilly’s focus was always on horary and prediction, not medicine.

Common Misconceptions About William Lilly

He was a magician. No. Lilly explicitly rejected ceremonial magic. He wrote that astrology was a natural science based on the influence of the heavens, not on spirits or demons. He was tried for witchcraft and acquitted because the court accepted his distinction.

He predicted the Great Fire of London. Partially true. In 1651, he published a pamphlet that mentioned “fire and sword” in connection with London. After the fire, people claimed he had predicted it. Lilly himself said the prediction was general, not specific. The chart he cast in 1666 (the one mentioned at the start of this article) was a private consultation, not a public prophecy.

He was a Parliamentarian propagandist. He was, but he also served royalist clients. After the Restoration, he adapted quickly and even cast a chart for Charles II’s coronation. His politics were flexible.

His methods are outdated. They are not. Horary astrology as practiced today follows Lilly’s rules almost unchanged. The only difference is that modern astrologers use computers instead of ephemeris tables.

FAQ

Is Christian Astrology still in print? Yes. Several editions are available, including facsimiles of the 1647 original and modern annotated versions.

Did William Lilly believe in magic? He did not. He argued that astrology was a natural science and that predictions came from observing planetary influences, not from invoking spirits.

What is the difference between horary and natal astrology? Horary answers a specific question by casting a chart for the moment the question is asked. Natal astrology interprets the birth chart of a person. Lilly focused almost entirely on horary.

The Legacy of a Practical Astrologer

William Lilly did not claim to be a prophet. He claimed to be a careful calculator of celestial influences. His legacy is not in the accuracy of his predictions (some were right, some were wrong) but in the system he codified. Every horary astrologer today, whether they know it or not, works in the shadow of Christian Astrology. The book survives because it is useful. The method survives because it works.

For those who want to go deeper, we have written a guide to horary astrology that walks through Lilly’s rules with modern examples. The glossary of astrological terms explains the technical vocabulary he used. And the astrology vertical hub collects our resources on the tradition Lilly helped preserve.