After 400+ years of a Dark Age for the Fae, the Moon Landing in 1969 either brought about the Resurgence, or was the product of the re-opening of the ways between the mundane world and the mythic. With a wave of Fae coming out of hiding from Arcadia (mostly sidhe, but some of the Commoner kith and a few of the rarer kiths as well), access between the mundane world and the Dreaming was re-established and the theory of reconnecting to Arcadia became closer to fact (although still conjecture).
For the 400 plus years of the Interregnum, the Kithain huddled in what few places of Glamour they could find and whispered about the coming of the Endless Winter and the triumph of Banality. Science and Reason continued to destroy the mysteries of the world and organize and systematize reality.
Until a miracle occurred.
On July 21, 1969, millions of people across the globe saw, on their televisions, astronauts land on the moon. Glamour rocked the world as it was released from confinement with the return of Wonder to so many people simultaneously. From science came forth magic, if only for a moment. That moment was enough.
Deep in the Dreaming, the rebirth of Glamour resounded in Arcadia and reopened trods that had slept since the Shattering. Lost freeholds reappeared as the Sons of Adam and Daughters of Eve dreamed of walking on the moon. The sidhe returned to a world very different from what they left, many as exiles for crimes committed by their houses; the Mists clouding their memories of what they had done.
The surge of Glamour, though, couldn't stand long against centuries of disbelief and the doors to Arcadia slammed shut once again. The sidhe, who did not know the Changeling Way and having no protection against Banality, had to take up the old ways of replacing the souls of mortals with their own faerie essence, sending those souls back through the portals before they closed to a fate they could not guess at. Most sidhe still practice this soul swapping method to this day. At other times they take up residence in infants and young children and their souls exist in a form of symbiosis.
While the Resurgence happened all over the world, the sidhe returned mostly to places with strong ties historically to Glamour: the British Isles and other places in Europe, but most of them ended up in America, attracted by the Summer of Love and the beacon of Glamour produced by it. The Nobles moved quickly to reclaim old freeholds and sent out a Clarion call to summon the Commoner fae to them again, expecting to pick up right where they had left off as rulers of the fae.
They were met with unexpected opposition from the Commoners who had lived centuries without their leadership. They had new leaders, those who wanted leaders, and many did without leaders at all. The feudal system was a thing of the past and other human political forms had taken its place. While a few rallied around the nobility, others rebelled and an uneasy period of political maneuvering began which culminated in an event that stained the nobility forever.
The sidhe in North America summoned Commoner leaders to a meeting on Beltaine to strike an accord. Instead these fae were met with cold iron and complete slaughter, an event that came to be known as the Night of Iron Knives. All hope for peaceful settlement ended there and led to the Accordance War.