According to the 'Enlightenment thinkers', starting with the redoubtably ignorant Petrarch, all was 'Dark' and opaque before 1550. Then suddenly, magically, the world of 'science', 'evolved' and man was freed. Thanks to Islam, Voltaire and Darwin, mankind's rationality was enabled, casting off 2000 years of oppression, fear, superstition and dirty stupidity. Which is why of course during said period, there were such monumental achievements as hospitals, eye glasses, chimneys, the blast furnace, science, math, public schools, art, polyphonic music, orchestras....
Brunelleschi's early 15th century dome in Florence is yet another example of unparalleled genius in the Middle Ages. Of course the 'Renaissance' claims this to be their own, as if this period of development was divorced from, and antagonistic to, what came before it. For the phase theologians of the not-so-Enlightened period; the time frames of the Middle Ages are very fluid indeed. Giotto's 3-D artwork from the early 14th century, along with Dante and sundry technologies such as wind-mills, are routinely categorized as part of the 'Renaissance'. Such fraudulent posturing is called 'factual'.
Brunelleschi’s Florentine dome, started in 1419, is situated firmly within the Medieval period, an era of great progress and wealth creation; and is the largest masonry dome ever built and is an astonishing 45 meters wide. It was created in part to supersede Justinian's enormous 6th century dome in the Haggia Sophia in Constantinople. The complexity of the project was staggering and it took more than 100 years from the original idea in 1296, to 1419, to start the affair. In fact even today, we don't fully understand how Brunelleschi achieved his masterpiece.
“Perhaps the most haunting mystery is the simplest of all: How did Brunelleschi and his masons position each brick, stone beam, and other structural element with such precision inside the vastly complex cathedral—a task that modern architects with their laser levels, GPS positioning devices, and CAD software would still find challenging today?”
Brunelleschi's dome was built squarely in the Middle Ages. But don't expert to hear 'experts' and quackademics admit that fact. They will simply move the 1419 project to the 'Renaissance'. Anything to avoid the obvious and anything to inure the cult of the Enlightenment from criticism.
History of the Dome is here