Short answers, pulled from the story.
The first embryonic surfaces of the Azores appeared in the waters of Santa Maria during the Miocene epoch around 8 million years ago. Pico Island rose most recently at 0.27 million years ago.
A captain sailing for Prince Henry the Navigator possibly discovered the Azores in 1427 though records remain uncertain. Settlement began in 1439 with migrants from mainland Portugal arriving mainly from Algarve and Alentejo provinces.
King Philip II of Spain claimed the throne following the dynastic crisis that followed the death of Cardinal-King Henry in 1580. Azoreans resisted Spanish attempts to conquer the islands including specifically at the Battle of Salga while António Prior of Crato was acclaimed King of Portugal on the 19th of July 1580.
There were 28 registered volcanic eruptions from the 15th century onward with fifteen occurring on land and thirteen happening beneath the sea. The last significant eruption took place off the coast of Faial in 1957 forming the Capelinhos volcano.
The Azores became the Autonomous Region of the Azores in 1976 after the Carnation Revolution of 1974 deposed the Estado Novo dictatorship in Lisbon. From 1836 to 1976 the archipelago was divided into three districts reflecting mainland administrative divisions rather than natural island groups.