Who were the Fallen Angels?

So you would think that if the Bible tells us that "sons of God" came down to the earth, and took "daughters of man" as wives, and their children were heroes and men of name, then we should have heard some stories about that. Well, you have, today as I am writing this it is a Thursday, which is Thor's Day, and I used to enjoy his adventures in Marvel Comics when I was a boy.
These guys are remembered as gods, from Scandinavia through Rome and Greece and out to India; and with similar stories but with different names. I have a translation of the Five Books of Moses by Robert Alter and he mentions in his footnotes that there is a similarity in the Bible story with the Greek mythology where divine beings also have a taste for sex with attractive women. He suggests perhaps a connection with Hittite mythology. He doesn't consider Enoch as a source because modern academics don't believe the book is old enough - see my comments here.

There is another very ancient book, from India, called the Mahabharata, which possibly describes the world being run by the children of the fallen angels. It is a world of many small kingdoms fighting wars with various advanced weapons that they had inherited from some earlier times. These are described as "celestial weapons" such as the Bhargava missile which releases thousands of arrows onto the enemy, and seemingly a nuclear missile called Brahmastra.

Below are some links from Wikipedia:

Vedic lore contains numerous elements which are common to Indo-European mythological traditions, like the mythologies of Persia, Greece, and Rome, and that of the Celtic, Germanic, Baltic and Slavic peoples. The Vedic god Indra in part corresponds to Dyaus Pitar, the Sky Father, Zeus and Jupiter or Perun. The deity Yama, the lord of the dead, is Yima of Persian mythology. Vedic hymns refer to these and other deities, often 33, consisting of 8 Vasus, 11 Rudras, 12 Adityas, and the late Rigvedic Prajapati. These deities belong to the 3 dimensions of the universe/heavens, the earth, and the intermediate space. Some major deities of the Vedic tradition include Indra, Surya, Agni, Ushas, Vayu, Varuna, Vishnu, Mitra, Aditi, Yama, Soma, Sarasvati, Prithvi, and Rudra

List of Greek mythological figures

Family tree of the Greek gods

Twelve Olympians

List of Roman deities

Norse mythology

List of Germanic deities

There are also the associated giants :-

Thor (Marvel Comics)

Thor from Marvel Comics and Ishtar from an ancient temple in Iraq