The Dutchman, who has been linked with the position since David Moyes was relieved of his duties in April, will assume control of the Old Trafford outfit after leading his country at the 2014 FIFA World Cup in Brazil.
Van Gaal's distinguished coaching career has seen him win domestic titles in his native Netherlands, Spain and Germany with Ajax, Barcelona and Bayern Munich respectively, as well overseeing Ajax's UEFA Champions League victory in 1994-95.
The 62-year-old will now be tasked with turning United's fortunes around following Moyes' ill-fated 10-month spell at the helm, which resulted in them relinquishing their Premier League title and failing to qualify for next season's Champions League.
The club's Premier League title defence never materialised, ending the season in seventh position, and a failure to secure Champions League football for next season proved the final straw for the club's owners.
