golden age

from The American Heritage® Dictionary of the English Language, 4th Edition

• n. A period of great peace, prosperity, and happiness.
• n. Greek & Roman Mythology The first age of the world, an untroubled and prosperous era during which people lived in ideal happiness.

from Wiktionary, Creative Commons Attribution/Share-Alike License

• n. A happy age of peace and prosperity.
• n. A time of great progress or achievement in a particular field.
• n. The Golden Age.

from the GNU version of the Collaborative International Dictionary of English

• adj. That period in the history of a literature, etc., when it flourishes in its greatest purity or attains its greatest glory; as, the Elizabethan age has been considered the golden age of English literature.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• n. any period (sometimes imaginary) of great peace and prosperity and happiness
• n. (classical mythology) the first and best age of the world, a time of ideal happiness, prosperity, and innocence; by extension, any flourishing and outstanding period
• n. a time period when some activity or skill was at its peak