In 1558 the Portuguese established a small garrison with a ''Viador'' (''Viyazoru''), or overseer of a factory (trading post) in the Maldives, which they administered from their main colony in Goa. Their attempts to impose Christianity provoked a local revolt led by Muhammad Thakurufaanu al-A'uẓam and his two brothers, that fifteen years later drove the Portuguese out of Maldives. This event is now commemorated as National Day.