6 Added History citings to support the answer.
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The founders of Hogwarts had funds from different people but did not have funding from any form of government.

The Wizard card of Helga Hufflepuff as per old JKR website is a as follows,

"[s]he brought people from different walks of life together to help build Hogwarts and was loved for her charming ways."

As per the establishment of Ministry of Magic, it is termed as 1707 in pottermore

The Ministry of Magic was formally established in 1707 with the appointment of the very first man to hold the title 'Minister for Magic', Ulick Gamp.
Prior to 1707, the Wizards' Council was the longest serving (though not the only) body to govern the magical community in Britain. After the imposition of the International Statute of Secrecy in 1692, however, the wizarding community needed a more highly structured, organized and more complex governing structure than they had hitherto used, to support, regulate and communicate with a community in hiding. Only witches and wizards who enjoyed the title of 'Minister for Magic' are included in this entry.

The establishment of The Wizards Council is unclear but it was not mentioned before 1269 anywhere, so we can assume it is not yet formed during the establishment of Hogwarts, which was in/before 933

The Wizards' Council was the predecessor to the Ministry of Magic (FBx). Barberus Bragge was the Chief of the Council in 1269.

The establishment of Hogwarts was due to the growing mistrust on the part of muggles. So, the founders wouldn't ask the muggle government for soft-funding.

Also, the history of Britain during the establishment of Hogwarts is very disturbed because of Viking invasions, we can assume that during this war between Alfred of Wessex and Vikings, the wizards of England region felt threatened and started moving into secrecy.

Late in the 8th cent., and with increasing severity until the middle of the 9th cent., raiding Vikings (known in English history as Danes) harassed coastal England and finally, in 865, launched a full-scale invasion. They were first effectively checked by King Alfred of Wessex and were with great difficulty confined to the Danelaw, where their leaders divided land among the soldiers for settlement. Alfred's successors conquered the Danelaw to form a united England, but new Danish invasions late in the 10th cent. overcame ineffective resistance . The Dane Canute ruled all England by 1016. At the expiration of the Scandinavian line in 1042, the Wessex dynasty (see Edward the Confessor) regained the throne. The conquest of England in 1066 by William, duke of Normandy (William I of England), ended the Anglo-Saxon period.

The founders of Hogwarts had funds from different people but did not have funding from any form of government.

The Wizard card of Helga Hufflepuff as per old JKR website is a as follows,

"[s]he brought people from different walks of life together to help build Hogwarts and was loved for her charming ways."

As per the establishment of Ministry of Magic, it is termed as 1707 in pottermore

The Ministry of Magic was formally established in 1707 with the appointment of the very first man to hold the title 'Minister for Magic', Ulick Gamp.
Prior to 1707, the Wizards' Council was the longest serving (though not the only) body to govern the magical community in Britain. After the imposition of the International Statute of Secrecy in 1692, however, the wizarding community needed a more highly structured, organized and more complex governing structure than they had hitherto used, to support, regulate and communicate with a community in hiding. Only witches and wizards who enjoyed the title of 'Minister for Magic' are included in this entry.

The establishment of The Wizards Council is unclear but it was not mentioned before 1269 anywhere, so we can assume it is not yet formed during the establishment of Hogwarts, which was in/before 933

The Wizards' Council was the predecessor to the Ministry of Magic (FBx). Barberus Bragge was the Chief of the Council in 1269.

The establishment of Hogwarts was due to the growing mistrust on the part of muggles. So, the founders wouldn't ask the muggle government for soft-funding.

The founders of Hogwarts had funds from different people but did not have funding from any form of government.

The Wizard card of Helga Hufflepuff as per old JKR website is a as follows,

"[s]he brought people from different walks of life together to help build Hogwarts and was loved for her charming ways."

As per the establishment of Ministry of Magic, it is termed as 1707 in pottermore

The Ministry of Magic was formally established in 1707 with the appointment of the very first man to hold the title 'Minister for Magic', Ulick Gamp.
Prior to 1707, the Wizards' Council was the longest serving (though not the only) body to govern the magical community in Britain. After the imposition of the International Statute of Secrecy in 1692, however, the wizarding community needed a more highly structured, organized and more complex governing structure than they had hitherto used, to support, regulate and communicate with a community in hiding. Only witches and wizards who enjoyed the title of 'Minister for Magic' are included in this entry.

The establishment of The Wizards Council is unclear but it was not mentioned before 1269 anywhere, so we can assume it is not yet formed during the establishment of Hogwarts, which was in/before 933

The Wizards' Council was the predecessor to the Ministry of Magic (FBx). Barberus Bragge was the Chief of the Council in 1269.

The establishment of Hogwarts was due to the growing mistrust on the part of muggles. So, the founders wouldn't ask the muggle government for soft-funding.

Also, the history of Britain during the establishment of Hogwarts is very disturbed because of Viking invasions, we can assume that during this war between Alfred of Wessex and Vikings, the wizards of England region felt threatened and started moving into secrecy.

Late in the 8th cent., and with increasing severity until the middle of the 9th cent., raiding Vikings (known in English history as Danes) harassed coastal England and finally, in 865, launched a full-scale invasion. They were first effectively checked by King Alfred of Wessex and were with great difficulty confined to the Danelaw, where their leaders divided land among the soldiers for settlement. Alfred's successors conquered the Danelaw to form a united England, but new Danish invasions late in the 10th cent. overcame ineffective resistance . The Dane Canute ruled all England by 1016. At the expiration of the Scandinavian line in 1042, the Wessex dynasty (see Edward the Confessor) regained the throne. The conquest of England in 1066 by William, duke of Normandy (William I of England), ended the Anglo-Saxon period.

5 improved formatting
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ThereThe founders of Hogwarts had funds from different people but did not have funding from any form of government.

The Wizard card of Helga Hufflepuff as per old JKR website is no canonical information on whether the founders have funded the school themselves or not, but we can have a brief idea from canon on whether they had funding.as follows,

"[s]he brought people from different walks of life together to help build Hogwarts and was loved for her charming ways."

The Hogwarts was established before the year 933 byAs per the four founders on accountestablishment of growing distrustMinistry of muggles. They did not receive any funding from governmentMagic, as the Ministry for magic came into existence in late 1600's, it is impossible for them to fund. It's predecessor, The Wizards Council also has no mentiontermed as 1707 in books before 1269. pottermore

The Ministry of Magic was formally established in 1707 with the appointment of the very first man to hold the title 'Minister for Magic', Ulick Gamp.
Prior to 1707, the Wizards' Council was the longest serving (though not the only) body to govern the magical community in Britain. After the imposition of the International Statute of Secrecy in 1692, however, the wizarding community needed a more highly structured, organized and more complex governing structure than they had hitherto used, to support, regulate and communicate with a community in hiding. Only witches and wizards who enjoyed the title of 'Minister for Magic' are included in this entry.

So itThe establishment of The Wizards Council is safe tounclear but it was not mentioned before 1269 anywhere, so we can assume that thereit is no specific form of government for witches and wizardsnot yet formed during the establishment of Hogwarts and people used to follow mostly muggle rules and regulations. But as the school was started because of muggle distrust, the founders won't go behind muggle government for funding.

So, we can conclude that there is no funding and no help from any governmentwhich was in building Hogwarts./before 933

The Wizards' Council was the predecessor to the Ministry of Magic (FBx). Barberus Bragge was the Chief of the Council in 1269.

Edit: According to JKR's website, Hufflepuff's wizard card states that "[s]he brought people from different walksThe establishment of life together to help build Hogwarts and was loved for her charming ways." You can check here asdue to the JKR website has been modified afterwardsgrowing mistrust on the part of muggles.

This clears So, the air that there isfounders wouldn't ask the muggle government for soft-funding involved in building Hogwarts by not only the Hogwarts-four but also of their friends.  

There is no canonical information on whether the founders have funded the school themselves or not, but we can have a brief idea from canon on whether they had funding.

The Hogwarts was established before the year 933 by the four founders on account of growing distrust of muggles. They did not receive any funding from government, as the Ministry for magic came into existence in late 1600's, it is impossible for them to fund. It's predecessor, The Wizards Council also has no mention in books before 1269.

So it is safe to assume that there is no specific form of government for witches and wizards during the establishment of Hogwarts and people used to follow mostly muggle rules and regulations. But as the school was started because of muggle distrust, the founders won't go behind muggle government for funding.

So, we can conclude that there is no funding and no help from any government in building Hogwarts.

Edit: According to JKR's website, Hufflepuff's wizard card states that "[s]he brought people from different walks of life together to help build Hogwarts and was loved for her charming ways." You can check here as the JKR website has been modified afterwards.

This clears the air that there is soft-funding involved in building Hogwarts by not only the Hogwarts-four but also of their friends.  

The founders of Hogwarts had funds from different people but did not have funding from any form of government.

The Wizard card of Helga Hufflepuff as per old JKR website is a as follows,

"[s]he brought people from different walks of life together to help build Hogwarts and was loved for her charming ways."

As per the establishment of Ministry of Magic, it is termed as 1707 in pottermore

The Ministry of Magic was formally established in 1707 with the appointment of the very first man to hold the title 'Minister for Magic', Ulick Gamp.
Prior to 1707, the Wizards' Council was the longest serving (though not the only) body to govern the magical community in Britain. After the imposition of the International Statute of Secrecy in 1692, however, the wizarding community needed a more highly structured, organized and more complex governing structure than they had hitherto used, to support, regulate and communicate with a community in hiding. Only witches and wizards who enjoyed the title of 'Minister for Magic' are included in this entry.

The establishment of The Wizards Council is unclear but it was not mentioned before 1269 anywhere, so we can assume it is not yet formed during the establishment of Hogwarts, which was in/before 933

The Wizards' Council was the predecessor to the Ministry of Magic (FBx). Barberus Bragge was the Chief of the Council in 1269.

The establishment of Hogwarts was due to the growing mistrust on the part of muggles. So, the founders wouldn't ask the muggle government for soft-funding.

4 Improved the answer
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There is no canonical information on whether the founders have funded the school themselves or not, but we can have a brief idea from canon on whether they had funding.

The Hogwarts was established before the year 933 by the four founders on account of growing distrust of muggles. They did not receive any funding from government, as the Ministry for magic came into existence in late 1600's,1600's, it is impossible for them to fund. It's predecessor, The Wizards Council also has no mention in books before 1269.

So it is safe to assume that there is no specific form of government for witches and wizards during the establishment of Hogwarts and people used to follow mostly muggle rules and regulations. But as the school was started because of muggle distrust, the founders won't go behind muggle government for funding.

So, we can conclude that there is no funding and no help from any government in building Hogwarts.

Edit: According to JKR's website, Hufflepuff's wizard card states that "[s]he brought people from different walks of life together to help build Hogwarts and was loved for her charming ways." You can check here as the JKR website has been modified afterwards.

This clears the air that there is soft-funding involved in building Hogwarts by not only the Hogwarts-four but also of their friends.

There is no canonical information on whether the founders have funded the school themselves or not, but we can have a brief idea from canon on whether they had funding.

The Hogwarts was established before the year 933 by the four founders on account of growing distrust of muggles. They did not receive any funding from government, as the Ministry for magic came into existence in late 1600's, it is impossible for them to fund. It's predecessor, The Wizards Council also has no mention in books before 1269.

So it is safe to assume that there is no specific form of government for witches and wizards during the establishment of Hogwarts and people used to follow mostly muggle rules and regulations. But as the school was started because of muggle distrust, the founders won't go behind muggle government for funding.

So, we can conclude that there is no funding and no help from any government in building Hogwarts.

Edit: According to JKR's website, Hufflepuff's wizard card states that "[s]he brought people from different walks of life together to help build Hogwarts and was loved for her charming ways."

This clears the air that there is soft-funding involved in building Hogwarts by not only the Hogwarts-four but also of their friends.

There is no canonical information on whether the founders have funded the school themselves or not, but we can have a brief idea from canon on whether they had funding.

The Hogwarts was established before the year 933 by the four founders on account of growing distrust of muggles. They did not receive any funding from government, as the Ministry for magic came into existence in late 1600's, it is impossible for them to fund. It's predecessor, The Wizards Council also has no mention in books before 1269.

So it is safe to assume that there is no specific form of government for witches and wizards during the establishment of Hogwarts and people used to follow mostly muggle rules and regulations. But as the school was started because of muggle distrust, the founders won't go behind muggle government for funding.

So, we can conclude that there is no funding and no help from any government in building Hogwarts.

Edit: According to JKR's website, Hufflepuff's wizard card states that "[s]he brought people from different walks of life together to help build Hogwarts and was loved for her charming ways." You can check here as the JKR website has been modified afterwards.

This clears the air that there is soft-funding involved in building Hogwarts by not only the Hogwarts-four but also of their friends.

3 Improved the answer
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2 Improved the answer
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