Unitatus was a secret society that was descended from UNIT, adopting a far more violent and xenophobic approach to their work, considering any alien as potentially violent where UNIT- thanks to the Doctor's influence- were willing to wait and learn if they were hostile rather than assuming it without proof. It was first active at least by the 26th century, where it suffered a devastating defeat when it tried to fight the Ferutu and a sizeable portion of their fleet was destroyed. Its actions nearly resulted in the destruction of Gallifrey and the erasure of this timeline when Medford believed that the Time Lords were attempting to invade the Earth Empire before the Fifth and Seventh Doctors managed to save their history. (PROSE: Cold Fusion) Unitatus survived at least until the 30th century, but by that point they were mainly known for organising bake sales and debating on whether 'Lethbridge-Stewart' was hyphenated or not. They were sometimes known to fight alongside the Empress' army. (PROSE: So Vile a Sin)