Now that we're gotten a handle on current theories about why humans developed larger penises in the first place—let's flip over the ol' sandglass and take a trip back in time.
Why You So Obsessed With
Talking about, drawing, carving, sculpting, and overall being kind of obsessed with big dicks is not a particularly new phenomenon. And what’s weird is that over the years we’ve associated big penises with fertility and sensuality, but also animalism and lasciviousness.
The earliest found depictions of penises date back to the Stone Age—like this cave painting from around 6000-5000 BC. You can see that what can be assumed to be the penis is uhhh enormous. Leg-sized. 
Cave Drawing; Anatolia 5000-6000 BC; 2017 Turkish Association of Urology
It’s not just penises, though. Vulvas and breasts were also more pronounced. Like the Venus of Willendorf, thought to be from around 28,000-25,000 BC. Archeologists have hypothesized that these overexaggerated depictions were early human ways of expressing beliefs about fertility and creation. 
Venus of Willendorf; Austria 28,000-25,000 BC; Public Domain
Let’s fast forward in time. Archeologists have discovered Egyptian scrolls from around 1000 BC depicting some VERY large penises in action. According to Egyptian mythology, Atum, the sun god, created other gods by masturbating—and this is an artistic rendition of Atum doing just that. 
Atum masturbating; Papyrus British Museum
In ancient India, the Kama Sutra depicts some of the first inklings of the “bigger is better” myth. One passage, relating to beliefs about relative sizes of genitals, reads: “Even in the medium ones, it is better for the man to be larger than the woman.” 
Kokopelli, a fertility deity recognized by some southwestern Native American tribes, was also depicted in some petroglyphs and pictographs as having a really big penis. Also known as a trickster, young girls have been known to fear him because sometimes he likes to either hand out unborn babies or straight up impregnate young women. 
Phallic Kokopelli; Public Domain
A change in tune
Things start to get a little more complicated in Greece around the 5th century BC. Similar to other cultures before them, large penises were copacetic. But fast forward a little, and they started attributing morality to penis size. The smaller, “ideal” penis can be seen in statues like this one of Zeus (or maybe Poseidon, jury's still out on that one) and, as the small penis trend in art carried on into the renaissance period, Michelangelo’s David. The main characters, the heroes, athletes, and Greek-liest of men had smaller, flaccid penises.
Bronze statue of Zeus or Poseidon; 460 BCE, Greece; Public Domain
Marble statue of David; Michelangelo 1504 AD, Italy; Public Domain
Meanwhile, big, erect penises were typically seen in art depicting Priapus, a god with a permanent erection and a foul mind, and satyrs, drunken, lustful half-goat men. While they were deities of fertility, they were also painted in an unfavorable light compared to their smaller-peened counterparts. [6,7]
Fresco of Priapus; 65-79 AD, Pompeii; Public Domain
Red-figured plate of a satyr; 520-500 BCE; Public Domain
Another prime example of how touchy Greeks were about penises: kyonodesme. Greeks used to hogtie their penises so they wouldn’t show in public, because that was considered shameful. The Romans later adopted something similar, called penile fibulae, which were like fancy dick barrettes; these were both a modesty thing and sometimes a chastity thing.
It’s assumed the Greeks (and eventually Romans) held these beliefs about penis size because they thought the ideal man was intellectual and logical, not lustful—and apparently big penises didn’t scream “intellectual.”
setheverman 2016; tumblr
That, and they were warring with surrounding nations who were more penis-positive. They called these people barbarians—which didn’t used to have the meaning it does today; initially “barbarian” just meant someone who doesn’t speak Greek. And thus foolishness, animalism, and “otherness” was associated with big penises. These ideals carried over into their art, and small penises became the artistic norm throughout much of Europe for centuries to come.
This marks a significant change, where the penis starts having a religio-political agenda, specifically in Europe. With the widespread rejection of hedonism (RIP, Roman Empire) and rise of monotheism in the Middle Ages, large penises aren’t ever really seen again in a positive light—unless it was symbolic.
For instance, the Bayeux Tapestry, a 230 ft-long tapestry from the 11th century depicting the Norman Conquest. There are very few visible human penises, and when they are, they’re large and depict heinous acts or stories of betrayal, and are never the main subjects of interest. Meanwhile, there are lots of horse penises, and historians have interpreted their relative sizes and erect-ness as a symbol of the power the man riding the horse held. Symbols of large penises, not large human penises themselves, were seen as positive and powerful.
Harold's Death; Bayeux Tapestry; Public Domain
Another example of this is codpieces. In 15th century Europe, codpieces, or pieces of fabric meant to house the penis started as functional, and quickly morphed into the symbolic. Codpieces grew larger and fancier in the 16th century, the height of chivalry. They became pieces of fashion as a means to communicate how “manly” you were. I mean, look at this thing. He’s not about to play lacrosse. What’s that thing for, sir?
Portrait of Antonio Navagero; Giovanni Battista Moroni 1565; Public Domain
As a quick note, penis sheaths and covering are not unique to Europeans, there are tons of cultures the world over who have had fancy penis coverings, from penis gourds to nambas.[13, 14] For the sake of this piece, we’re sticking to Europeans and eventually the United States.
Let’s fast forward to the French Revolution of the late 1700s. The people hated Marie Antoinette because she was a symbol of the monarchy, and sexual defamation propaganda was spread wide and far. The people were critical of General Lafayette as well, also seen in the images below, because he was sympathetic to both the common people and the crown, sometimes seen as foolish, rude, and a hick. Given the recent archeological discoveries in Pompeii, the people of the revolution were likening Lafayette to a Roman hedonist—meaning, that big dick wasn’t really a good thing. The whole point of these was to ridicule The Crown & Friends, and promote revolution and reform because they were crude and foolish.
(Fun Fact: Marie Antoinette pretty publicly disliked General Lafayette.)
Through our brief history lesson, we’ve learned that drawings and sculptures of big penises are nothing new, but their meaning certainly has changed over time. What began as expressions of fertility, ended in big penises symbolizing brutishness and foolishness. Strangely enough, we also started to see the beginnings of the idea that penis size=power and masculinity.
Stay tuned for part 3, where we’ll talk about Freud, witches, Big Dick Energy, and a surprisingly tender subreddit.