'In Slytherin
You'll make your real friends,
Those cunning folks use any means
To achieve their ends.'

'power-hungry Slytherin
Loved those of great ambition'

***

'Shrewd Slytherin, from fen'

'Said Slytherin, "We'll teach just those
Whose ancestry's purest."'

'Slytherin
Took only pure-blood wizards
Of great cunning just like him.'

~ Various songs of The Sorting Hat

Slytherin's reputation is a fierce one to be sure, but while this may be true, there are still a lot of misconceptions to be explored about both the house and man himself.

The Slytherin house is famous for producing the most 'Dark' witches and wizards of all time, however, with famous Dark Servants such as the Gryffindor Peter Pettigrew, to what extent is it fair to pin the weight of this blame on Slytherin? It must be considered that he-who-must-not-be-named once went to Hogwarts School, and was himself a Slytherin. Those who would have known him as a charming boy and then been recruited by him would naturally have been drafted from Slytherin, and no one can say if Tom Riddle had been the member of another house that their reputation would not have suffered similarly.

What is often overlooked is how many 'good' witches and wizards the Slytherin house has produced. Horace Slughorn, who defended the school during the Battle of Hogwarts, and Andromeda Tonks, mother of Nymphadora Tonks, are both Slytherins who renounce the pure blood supremacy attitude so often associated with the house. The Slytherin Regulus Black died attempting to destroy the Dark Lord. During the battle of Hogwarts, a number of Slytherin students returned to the school to defend it, despite possibly knowing a number of the people they fought against, which takes true courage and fortitude. The great and powerful Merlin, who opposed the dark witch Morgana, and created the Order of Merlin to protect muggles from harmful uses of magic, was a brilliant and compassionate Slytherin, who may have been taught by the great Salazar himself.

It is striking to think of the great and good Merlin being taught by Salazar Slytherin, who famously wanted to refuse muggle borns entry into the school, even to the extent of leaving the school with bad blood. To understand Slytherin's motivations, I believe we must consider the particular time in which the school was built. Though his stance on the admittance of muggleborn students was wrong, I think to make this his legacy is worse, and to misunderstand it.

The Sorting Hat has said that in the House of Slytherin you can make your real friends, highlighting the loyalty of Slytherin. Perhaps Salazar retained this loyalty long after he left, ever ready to protect it if it turned out he was right. Wizard-Muggle relations at the advent of the school had reached a violent peak; consider the frequent witch burnings as an example. His intention to refuse entry to the muggle-born students at the time was born out of a war with muggles, to whom muggle-borns are inherently related, and not the belief that they are in anyway magically inferior. As he was overruled by the other founders on this matter, being directly opposed by Hufflepuff who admitted anyone of magical ability who wanted to learn, it is my personal belief that the Chamber of Secrets was build to house the students in the event of an attack by muggles. The basilisk, under his control, would have protected them in this case. Salazar was never known to have caused harm to muggles or muggle-borns, and his basilisk only did so under the command of the Dark Lord centuries later. With this in mind, the pureblood supremacy that is associated with the house seems to have become far removed from context after a millenium, which is hardly surprising.

Slytherin House in modern times has dropped the pureblood requirement, with mixed heritage wizards such as Severus Snape becoming notable members, giving further evidence to the idea that what Slytherin valued was not pure bloodedness for its own sake, but security in a violent time that has long passed. And, as mentioned previously, notable Slytherins have opposed this attitude. If we are agreed that we trust the Sorting Hat to represent the values of the founders, then it's clearly beyond time to hold individuals accountable for their backwards beliefs, and not ascribe them to a house they do not represent.

'And at last there came a morning
when old Slytherin departed
and though the fighting then died out
he left us quite downhearted.

...though condemned I am to split you
still I worry that it's wrong'

~ The Sorting Hat

Since the famous falling out, the Sorting Hat itself speaks out in favour of much greater unity. Perhaps, if we can overcome the stereotypes and misconceptions we associate with each house, we can finally, after all this time, unite, and grow to be the multidimensional witches and wizards we are supposed to be; finally correcting the wrongs of our magical ancestors, and creating a rich Hogwarts legacy to truly bring true honour and greatness to our school.

Regardless, the House now belongs to those of whom it consists. It is up to them to redefine it as they wish!