Weren't they originally because people were paid Daily and as the banks were closed so we're the factories.
No but google is your friend.
Origins of bank holidays
Prior to 1834, the Bank of England observed about 33 saints' days and religious festivals as holidays, but in 1834, this was reduced to just four: 1 May, 1 November, Good Friday, and Christmas Day.
In 1871, Sir John Lubbock introduced the Bank Holidays Act, it introduced the concept of holidays with pay and designated four holidays in England, Wales and Northern Ireland, and five in Scotland. These were Easter Monday, the first Monday in August, the 26th December, and Whit Monday (England, Wales and Northern Ireland) and New Year's Day, Good Friday, the first Monday in May, the first Monday in August, and Christmas Day (Scotland). In England, Wales and Ireland, Good Friday and Christmas Day were considered traditional days of rest (as were Sundays) and therefore it was felt unnecessary to include them in the Act. The move was such a popular one and there were even suggestions that August Bank Holiday should be called St Lubbock's day!
In Ireland, in 1903, the Bank Holiday (Ireland) Act added 17 March, Saint Patrick's Day, as a bank holiday, and in 1926 the Governor of Northern Ireland proclaimed 12 July (Anniversary of the Battle of the Boyne in 1690) as a bank holiday too. This particular holiday is proclaimed annually by the Secretary of State for Northern Ireland.
In 2006, the Scottish Parliament designated St Andrew's Day, November 30, as an official bank holiday in Scotland. But there is no public holiday for St David's Day in Wales, or St George's Day in England.
From 1965 the date of the August bank holiday was changed to the end of the month in England, Wales, and Northern Ireland. The Whitsun bank holiday (Whit Monday) was replaced by the late spring bank holiday - fixed as the last Monday in May.
Bank holidays today
The Banking and Financial Dealings Act 1971, is in force today and there are 8 permanent bank and public holidays in England and Wales, 9 in Scotland and 10 in Northern Ireland.