This picture is a woodcut made by Hans Glaser, 'a very frightful spectacle', seen in the morning sky over Nuremberg,  Germany, on April 4, 1561. 

A case from 1561:

Between 1561 and 1566 residents of Nuremberg, Germany and Basel, Switzerland witnessed spectacular displays of spheres, disks and tubes zooming about the sky and engaging in an aerial ballet.

Woodcut of an Aerial Battle Over Nurnberg, now Nuremberg, Germany on April 4, 1561 - Some planes have crashed. As a result of religious interpretation, medieval artists interpreted fuselages and wings as crosses, and rockets became tubes full of balls. 

Note that two people seem to be witnessing a crash of at least one of these flying object.

At dawn of April 4, in the sky of Nuremberg (Germany), a lot of men and women saw a very alarming spectacle where various objects were involved, including balls "approximately 3 in the length, from time to time, four in a square, much remained insulated, and between these balls, one saw a number of crosses with the color of blood. Then one saw two large pipes, in which small and large pipes, were 3 balls, also four or more. All these elements started to fight one against the other." (Gazette of the town of Nuremberg).

The events lasted one hour and had such repercussions that an artist, Hans Glaser, drew a woodcut of it at the time. It describes two immense black cylinders launching many blue and black spheres, blood red crosses, and flying discs. They seem to fight a battle in the sky, it also seems that some of these spheres and objects have crashed outside the city. - Source

This picture details the events of August 7, 1566, in Basel, Switzerland. The spheres appeared at sunrise, 'Many became red and fiery, ending by being consumed and vanishing', wrote Samuel Coccius in the local newspaper on this date. A 16th century woodcutting depicts a scene in which dark spheres were witnessed hovering over the town of Basel, Switzerland in 1566

An observation in 1566:

Between 1561 and 1566 residents of Nuremberg, Germany and Basel, Switzerland witnessed spectacular displays of spheres, disks and tubes zooming about the sky and engaging in an aerial ballet.

On August 7, 1566, at dawn, many citizens of Basle (Switzerland), frightened, saw during several hours the black spheres involved in a formidable aerial battle, invading the sky of their city: "at the time when the sun rose, one saw many large black balls which moved at high speed in the air towards the sun, then made half-turns, banging one against the others as if they were fighting a battle out a combat, a great number of them became red and igneous, thereafter they were consumed and died out," wrote Samuel Coccius, the student in "crowned writings and liberal arts" who consigned the strange events in the city's gazette. - Source

AD 830 and 833, Lyons, France:
Historical record states that several "wonderfully constructed aerial ships" appeared over  Lyons, France between 830 and 833 AD. These ships were witnessed by hundreds of people, a few of which were taken aboard the crafts. Archbishop Agobard rescued and later  interviewed a small group of abductees who were attacked by frightened mobs upon their return.

AD 842, France:
Multicolored armies were seen marching in the sky...These sightings of infernal armies were nocturnal. They several times accompanied the siege of Jerusalem.

AD 919, Hungary:
Spherical objects shinning like stars, bright and polished, were reported going to and fro in the sky.

AD 927, the town of Verdum, France:
The whole Eastern part of France saw fiery armies in the sky. During these times of Charlemagne there were 'penalties against creatures that travel in aerial ships. 3 people who came down from one of these ships were 'crazy enough to call themselves wizards', the mob of people who witnessed their descenct killed these people and the bodies were nailed to boards and were placed in the river.

AD 1254, January 1, at St. Alban's Abbey:
At midnight, in a serene sky and clear atmosphere, stars shinning and the moon 8 days old, there suddenly appeared a large ship, elegantly shaped, well equipped and of marvelous color.

AD 1461, November 1:
A strange object shaped like a ship, from which fire was seen flowing, passed over the town Arras, France.

AD 1752, Augermanland Sweden:
Luminous shperes were seen coming out of a bright cylinder.

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UFOs were frequently seen over England and France in the 8th and 9th centuries. Charlemagne, Emperior of France, called them the "evil spirits of the air."

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According to legends told throughout Europe for thousands of years, the Incubus and the Sucubus (small male and female "demons") visit people in the night for sexual encounters.  How similar is this to modern-day cases involving aliens taking egg and sperm samples from unwilling participants in the middle of the night?

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Alexander the Great reported witnessing UFOs observing one of his battles from the air.
The following passage was translated from Egyptian hieroglyphics dating back to the 15th century BC ...
"A circle of fire coming in the sky, noiseless, one rod long with its body and one rod wide. After some days these things became more numerous, shining more than the brightness of the sun."

* * *
Part of the annals of Thutmose III, who reigned around 1504 - 1450 B.C., records what appears to be a fleet of flying craft. They were described as "a circle of fire that was coming in the sky...It had no head, the breath of its mouth had a foul odor. Its body one rod long and one rod wide. It had no voice." Following this sighting, many others followed as the papyrus goes on.  - SOURCE

Found on the Temple ceiling at Abydos;

The hieroglyphics above are taken from an Egyptian tomb.  Note the modern jet like glyph, the helicopter on the left, surprising since this artwork is more than 5,000 years old.

A 3,400 year old papyrus scrolls belonging to Egyptian Pharoah Thutmose III describe a group of fiery circles that were seen flying through the sky over his army.

In AD 400, Panodorus, an Egyptian monk wrote:

"From the creation of Adam, indeed down to Enoch and to the general Cosmic Year 1,282, the number of days was known in neither month nor year but the Egregori ('watchers' or 'angels') descended to Earth in the general Cosmicm Year 1,000, held converse with men and taught them that the orbits of the two luminaries being marked by the 12 signs of the Zodiac are composed of 360 parts."

In AD 1027, August, Cairo:
Numerous noisy objects were reported.

The following passage was translated from Egyptian hieroglyphics dating back to the 15th
     century BC ...

     "A circle of fire coming in the sky, noiceless, one rod long with its body and one rod wide. After
     some days these things became more numerous, shining more than the brightness of the sun."