Eton Montem (or ad Montem – literally to the Mountain) was a custom observed by Eton College from at least 1561 until it was finally suppressed in 1847, at the Montem Mound (or Salt Hill) in Chalvey, Slough, Buckinghamshire (later Berkshire). The mound is situated some 2 miles from the college near the London to Bath coach road, now the A4.
Montem is first reported in William Malim's consuetudinarium (book of customs) of 1561, when it seems to have been an initiation ceremony for new boys, who were scattered with salt (which can mean 'wit' as well as 'salt') at the mound.
By the 18th century, the ceremony had changed to a glorified flag day. Salt was no longer scattered on scholars; instead, pinches of salt and little blue tickets were sold to passers-by (the blue ticket – inscribed on alternate celebrations with 'Mos Pro Lege' or 'Pro More et Monte' – acted as a ticket of exemption from further contributions) for 'salt' – money that went towards the anticipated expenses of the Captain of the School (the senior Colleger) at King's College, Cambridge. Collecting was restricted to two 'salt-bearers' (also senior boys at the college) and ten or twelve 'servitors' or 'runners' who between them covered all the roads around Eton and Windsor.
Until 1758, Montem was held annually in January. The timing was then moved to the more clement weather of Whitsun Tuesday and the festival became biennial. In 1778, the frequency was reduced further so that Montem was only celebrated once every three years.
As time passed, the event seems to have become bigger, becoming eventually a semi-military muster of the whole school. Crowds and royalty (including at various times Queen Charlotte, George IV, William IV, Queen Victoria and Prince Albert) flocked to see the event. Towards the end of the ceremony's life, more than £1000 would typically be collected in salt, but this was before expenses, leaving substantially less for the Captain of the School to take to university.