Mercator the Mapmaker
Biography
Imagine that you are given a map to find
your way from your home to a friend’s
house. When you try to follow it,
however, it leads you to the wrong place.
Even though you followed the map
exactly, the map was just plain wrong.
Now imagine that you are sailing across
the Atlantic Ocean, which is hundreds of
miles wide, with limited supplies. How
important do you think it is for the map
to be accurate in that case?
In the early Renaissance period,
European explorers faced a large
problem. As the explorers set out to find
new trade routes to Asia, there were no
reliable maps available. Although each
expedition that returned had more
details on the new lands discovered to
In 1569, Gerard Mercator created the first
the south and west, no one could quite
map of the world that used triangularization to
put it all together correctly. It was even
accurately measure distance.
more frustrating that the instruments of
navigation, namely the compass, could
not be used accurately. Ships that tried to measure distances on these maps
were landing hundreds of miles off course.
In 1568 Gerard Mercator created the Mercator projection map. The map
showed the entire world on a single piece of paper and made it possible for
sailors to chart straight lines to help direct their exploration. Let’s take a look
at the man who changed the course of European exploration.
Born on March 5, 1512, Gerard Kremer lived in Flanders, which is modern day
Belgium. His parents were fairly poor. His father was a shoemaker and farmer.
However, Gerard’s uncle had been educated as a priest. At this time, priests
were also considered philosophers. Gerard’s uncle valued education and
helped young Gerard enroll in school, where he learned Latin, math, and
religion. At age 15, Gerard entered the monastic school in the Netherlands to
train for the priesthood like his uncle. At this point, Gerard’s life took an
interesting turn.
As a way to teach penmanship, the school gave students sacred texts to copy.
Through this method of learning, Gerard was exposed to the ancient
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Mercator the Mapmaker
Biography
philosophers. He became especially interested in the geographical works of the
ancient scholar Ptolemy. In 1527, after his mother unexpectedly died, Gerard’s
father sent him away to continue his schooling. It was at this point that Gerard
changed his last name from Kremer to the name we recognize today: Mercator.
The word mercator means merchant in Latin. Three years later, in 1530,
Mercator enrolled in Louvain University, the same university his uncle had
attended.
At Louvain, Mercator attended mathematics and astronomy lectures given by
Gemma Frisius, a leading theoretical mathematician. His new scientific
education began to give Mercator doubts about his religious upbringing. He
was beginning to feel that the religious lessons from his childhood did not fit
with the mathematical and geographical lessons he was learning at university.
Specifically, he believed there were large differences between the Bible and the
writings of the ancient philosophers such as Aristotle. Both accounts had
different versions of how life on Earth originated, but he favored the biblical
account. From our modern perspective, these doubts may seem natural or
commonplace, but at the time, it was dangerous to question the value of
religion. In fact, such questioning could lead to one being charged with heresy,
or the denial of a religious belief. The punishment for heresy was
imprisonment or death by beheading, burning, or even being buried alive.
Mercator began to visit with geographers and priests across Europe. He may
have done this in an effort to prove his suspicions about the conflicting
accounts of geography in the Bible and from explorers. Either way, his trips
were crucial for his understanding of the world’s lands and for coming to terms
with his Christian beliefs.
As he traveled, Mercator learned engraving and instrument making. He also
continued to study astronomy with Frisius. Because he was not taught
astronomy as a young man, he had to learn a whole level of mathematics
before he could fully understand the relation of the stars and measure their
distances to Earth. The result of his studies can be seen on the first map he
created in 1537.
Mercator joined together geography and religion when he created a map of
Palestine that illustrated texts in the Bible. The next year, he made a map of
Flanders for Holy Roman Emperor Charles V. This map used a
triangularization method to accurately distance map points. This method
measured angles from known points to a baseline rather than point-to-point
distance measurement. He used this method for creating globes of Earth and
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Mercator the Mapmaker
Biography
also for measuring the distances to stars. In 1538 Mercator made a world map,
the first to identify North and South America as separate continents.
Mercator’s mapmaking skills were put on hold in 1544, when he was
imprisoned for heresy. At this time, Flanders was in the middle of a Catholic
effort to suppress the rising Protestant religion. His trips abroad and his
association with known Protestants made officials question his faith. He was
released seven months later after no evidence could be found to connect him
with famous heretics (who were burned at the stake). Louvain University
interfered as well, pushing for his release after nothing incriminating was
found in his home.
Mercator returned to his studies and began to teach mathematics. In 1569 he
published a book called Chronology, which attempted to create an accurate
world history that included political, Biblical, and scientific events. Because he
included heretics in his history, the book was banned by the Catholic Church.
That same year he created a map that changed everything.
The Mercator wall map, or
projection, was a diagram
of Earth made up of 18
pieces of paper. Others had
tried to map the world, but
they could not quite figure
out how to line up the land
correctly. Using Ptolemy’s
grid system, Mercator made
the lines of latitude and
longitude intersect at 90
degree angles, or
perpendicularly. Previous
The Mercator projection is the most well-known projection. The
maps often used diagonals
straight lines allow for continuous navigation along the earth. If
radiating from a central
a sailor followed a line, the compass would change but the
point on the equator. He
direction remains the same.
stretched the longitude and
latitude the same amount. The result was a map showing the curved lines of
Earth as straight lines. This made it easier for sailors to navigate accurately.
However, the Mercator projection was not perfect. Because it stretched lines
equally, landmasses and the poles became distorted. Where latitudes are
shorter, landmasses seemed larger because Earth is curved. On a Mercator
map, Greenland looks similar in size to Europe, even though it is 4.7 times
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Mercator the Mapmaker
Biography
smaller. This is because the northern part of Greenland is stretched. The
Mercator projection also places Europe at the center of the world—because for
Mercator, it was! He had always lived in Europe, so he naturally placed it front
and center.
The maps that Mercator designed changed geography and mapmaking forever.
After Mercator died in 1594, his son published his collection of maps under the
title Atlas, or Cosmographic Meditations on the Structure of the World. Just
as we still use the Mercator map as the basis of world maps, we use a word
from his title, “atlas,” when referring to a collection of maps.
Mercator held a variety of roles including scholar, teacher, engraver, and word
coiner. His most famous role remains that of cartographer. Although
cartography caused Mercator problems, like being charged with heresy, it
changed the way we view the world. His projection map will remain an
important part of history, known for inspiring explorations that increased what
we know about world geography.
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Mercator the Mapmaker
Biography
After reading the passage, answer the following questions:
1. Based on information presented in the passage, which is an example
of heresy?
A. holding an opinion different from established religious beliefs
B. attending church regularly and volunteering in the community
C. writing texts that support a government
D. believing in the power of the church
2. How was Mercator’s projection map different from other maps
produced at the time?
A. It showed that Africa was the smallest continent.
B. It included Australia which was just discovered.
C. It had straight lines instead of curved lines.
D. It marked Greenland as the center of Earth.
3. Why was Mercator not put to death for heresy?
A. He made a map of the prison.
B. He was too important to exploration.
C. The emperor demanded his release.
D. There was no evidence against him.
4. No one in the 1500s had traveled around the whole world, so of
course Mercator’s map would not have been perfect. How could the
inaccuracies of the Mercator map have affected exploration? Use
details the text to support your answer.
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