Legends of the Indar Sector

Many are the Legends of the Indar Sector, here are a few selected by the Adeptus Administratum for being either highly likely or confirmed.

Meru
Legend considered highly likely and elements have been confirmed

When the sector was first formed in the Great Crusade, Meru was its natural capitol. Legends say that the Emperor, along with members of the Ultramarines, White Scars and [REDACTED] met with the existing leaders of the sector here. Meru stood at a confluence of all the primary warp currents in the sector. Later, during the dark millenia of the sector, Meru was a bone of contention between the Vestan and Andu faiths, each declaring it holy. The Andu used its location in their territory as a claim to their rightness, while the Vestans used that to declare wars to take it back. Things came to a head in ??.M35?? when rogue elements from the Vestans attempted to deploy a Halo device in order to move Meru into their territory. The planet, along with its billions of citizens and the star it orbitted, simply vanished, and the warp currents thrashed around for centuries, making warp travel highly dangerous, until coming into something close to their modern configuration.

Breega
Legend confirmed, last recorded sighting of Breega in 746.M41

In the area now known as the Dona tributaries is a planet engulfed by the warp for a century (or more) at a time, in a sort of stasis, then brought into the Materium for a single year. Many legends of the planet were told (it is a planet of sorcerors, it is a planet engulfed in the worst of tek-heresies, it is a paradise you will go when you die), but the truth of the matter was discerned in 542.M41, when the planet sent out an astropathic message asking if the Imperium yet lived. An expedition led by an Explorator Magos and an Order Hereticus Inquisitor went to the planet. For them, a mere one hundred years has passed since the Heresy, and the old recall meeting elements of the Great Crusade as children. Investigation found a planet wide Gellar-stasis field, of theoretically impossible ability, and the Magos decided to stay on the planet, to further explore its values. Since then it has made two more appearances, once in 644.M41, and again in 745.M41, staying for roughly a year each time. The last message received from the planet was from the Magos, expressing his view that he had 'almost worked out' the secrets of this world. Many are looking forwards to the next time Breega reappears, in hopes of finding answers to this ancient mystery.

Dona
Legend considered highly likely and elements have been confirmed

During the era of conflict that led to the loss of Meru, Dona, long considered a skilled Diviner, and honored by the Andu with the title of 'Maharishi' (an honorific given to Primaris Psykers), she foresaw the chaos that would be caused, and started seeking out others who, like her, wished an end to these wars. Together they obtained hundreds of ships, both civilian and military, and, according to legend, evactuated a hundredth of Meru before it was lost. They filled the Dona Tributaries like a flood, and during the next few centuries, thousands of ships lost in the immaterium found their way to one of these planets and settled down. Dona appeared before each one of them while they were lost and asked them to give up their old rivalries and live simply, for the Emperor. Those who agreed found their way there.

The Witches of the Lost Tributaries
Legend unconfirmed, considered unlikely or misunderstanding.

Legend has it that a number of worlds in the Dona Tributaries are 'Lost', and come into the dominion of the Witches. The details change in every telling, but the witches are always sorcerers in thrall to some Daemonic Prince, and every nine years a tithe of every ninth child born in those years are taken, never to be seen again. Their powers, names, and origins vary in each telling, but the above elements are always constant.