June 21st, or there abouts, is celebrated as a holiday in the northern hemisphere; as it is closest to the sun at this point in the Earth’s rotation. This day is also considered a Sabbat to Wiccans and Neo-Pagans known as Litha. And as can be expected, regardless of tradition, this is a celebration about the powers of the sun.
Other holidays that are celebrated on this Solstice are: Tiregān, Jāņi , Kupala Night and Midsummer.
Tiregān is an ancient Persian festival. The festival refers to the archangel Tir (arrow) or Tishtar (lightning bolt) who appeared in the sky to generate thunder and lightning for much needed rain. Legend says that Arash Kamangir Amoli was a man chosen to settle a land dispute between the leaders of two lands, Iran and Turan. Arash was to loose his arrow on the 13th day of Tir and where the arrow landed, would lie the border between the two kingdoms. Turan – which had suffered from the lack of rain – and Iran rejoiced at the settlement of the borders, then rain poured onto the two countries and there was peace between them. And it should not be forgetten that Archangels originated with Zoroastrianism.
Jāņi is celebrated in Latvia. This is an ancient festival originally celebrated in honour of Latvian pagan deity Jānis, referred to as a “Son of God” in some ancient Latvian folksongs. Jāņi is thought to be the time when the forces of nature are at their most powerful, and the boundaries between the physical and spiritual worlds are thinnest. Another important detail is fire. A festival fire must be kept from sunset till sunrise, and various kinds of flaming light sources are used; usually these are bonfires,which traditionally people jump over to ensure prosperity and fertility.
Kupala Night, or Ivan Kupala Day (Feast of St. John the Baptist) is celebrated in Ukraine, Russia, Belarus and Poland. Some early mythology scholars claimed that the holiday was originally Kupala; a pagan fertility rite later accepted into the Orthodox Christian calendar. Many of the rites related to this holiday , due to the ancient Kupala rites, are connected with the role of water in fertility and ritual purification.On Kupala day, youth jump over the flames of bonfires in a ritual testing of one’s bravery and faith.
In most other European countries, and here in the Americas, it is simply known as Midsummer. All Midsummer-related holidays, traditions, and celebrations are pre-Christian in origin. Bonfires were lit to protect against evil spirits which were believed to roam freely when the sun was turning southwards again. Also, it was a time for magical plants and herbs to be procured such as Calendula and St. John’s Wort.
Excellent blog on Midsummer: