جزایر خرم (زبان یونانی: μακάρων νῆσοι) جزایری نیمهافسانهای در اقیانوس اطلس بود که قهرمانهای اساطیر یونانی از آنها به عنوان بهشت بدون زمستان یاد میکنند. در اساطیر یونانی این جزیرهها مختص کسانی است که سه بار دچار تناسخ شدهاند و هر سه بار به پاکی قضاوت شده و اجازه یافتهاند به الوسیون راه یابند. مفهوم برازیل در اسطورهشناسی سلتی نیز در مفهوم جزایر خرم یونانی تنیده شدهاست.
The Fortunate Isles or Isles of the Blessed (Greek: μακάρων νῆσοι, makárōn nêsoi) were semi-legendary islands in the Atlantic Ocean, variously treated as a simple geographical location and as a winterless earthly paradise inhabited by the heroes of Greek mythology. The related idea of Brasil and other islands in Celtic mythology are sometimes conflated with the Greek sense of islands in the western Mediterranean: Sicily, the Aeolian Islands, the Aegadian Islands or other smaller islands of Sicily. Later on the islands were said to lie in the Western Ocean near the encircling River Oceanus; Madeira, the Canary Islands, the Azores, Cape Verde, Bermuda, and the Lesser Antilles have sometimes been cited as possible matches.
According to Greek mythology, the islands were reserved for those who had chosen to be reincarnated three times, and managed to be judged as especially pure enough to gain entrance to the Elysian Fields all three times. A feature of the fortunate islands is the connection with the god Cronus; the cult of Cronus had spread and connected to Sicily, in particular in the area near Agrigento where it was revered and in some areas associated with the cult of the Phoenician god Baal.
Flavius Philostratus' Life of Apollonius of Tyana (v.2) says, "And they also say that the Islands of the Blessed are to be fixed by the limits of Libya where they rise towards the uninhabited promontory." In this geography Libya was considered to extend westwards through Mauretania "as far as the mouth of the river Salex, some nine hundred stadia, and beyond that point a further distance which no one can compute, because when you have passed this river Libya is a desert which no longer supports a population".
Plutarch, who refers to the "fortunate isles" several times in his writings, locates them firmly in the Atlantic in his vita of Sertorius. Sertorius, when struggling against a chaotic civil war in the closing years of the Roman Republic, had tidings from mariners of certain islands a few days' sail from Hispania:
It was from these men that Sertorius learned facts so beguiling that he made it his life's ambition to find the islands and retire there.
Pliny the Elder's Natural History adds to the obligate description—that they "abound in fruit and birds of every kind"—the unexpected detail "These islands, however, are greatly annoyed by the putrefying bodies of monsters, which are constantly thrown up by the sea".
The Isles are mentioned in Book II of A True History by the Greek satirist Lucian of Samosata. The author makes fun of the heroes residing there by giving an account of their petty squabbles as presented to the court of the magistrate, Rhadamanthus. He goes on to describe other observations of how the residents occupy their time, using every opportunity to satirise both contemporary life and Greek mythology.
Lucio Russo, in L'America dimenticata, puts forward the bold hypothesis (supported by means of statistical methods) that the Fortunate Isles were actually the Lesser Antilles and that Hipparchus knew their longitude with remarkable precision.