context: The earliest reliable information on European activity in Madeira's history dates back to the early 15th century. There are also much older but uncertain references to Madeira right from the start of the era. The official written history of Madeira began with the arrival of the Portuguese in 1418. The carnation revolution in Portugal in 1974 overthrew the military junta that ruled the country, which resulted in Madeira being granted autonomy two years later. Madeira joined the European Union in Portugal in 1986. Madeira's standard of living has risen during autonomy and EU membership. Madeira's President Miguel Albuquerque has been in office since March 2015. His predecessor, Alberto João Jardim, was in office for 37 years.
question: Why is Madeira an autonomous region?
answers.text: The carnation revolution in Portugal in 1974 overthrew the military junta that ruled the country, which resulted in Madeira being granted autonomy two years later